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                                                                   EXHIBIT 10-12



                              MCN ENERGY GROUP INC.
                               LONG-TERM INCENTIVE
                             PERFORMANCE SHARE PLAN



                    (AS AMENDED AND RESTATED OCTOBER 1, 1997)

















February 22, 1999



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                              MCN ENERGY GROUP INC.

                               LONG-TERM INCENTIVE
                             PERFORMANCE SHARE PLAN

                                Table of Contents
                                                                            Page
                                                                            ----

Article 1 - Title, Purpose and Effective Date............................... 1

     1.1      Title ........................................................ 1

     1.2      Purpose ...................................................... 1

     1.3      Effective Date................................................ 1

Article 2 - Definitions..................................................... 1

     2.1      Affiliated Company............................................ 1

     2.2      Award......................................................... 1

     2.3      Board of Directors............................................ 1

     2.4      Cause ........................................................ 2

     2.5      Code ......................................................... 2

     2.6      Committee..................................................... 2

     2.7      Common Stock.................................................. 2

     2.8      Corporation .................................................. 2

     2.9      Deferred Account.............................................. 2

     2.10     Disability ................................................... 2

     2.11     Key Employee.................................................. 2

     2.12     Nonemployee Director.......................................... 2

     2.13     Participant .................................................. 2

     2.14     Participating Corporation..................................... 2

     2.15     Peer Group.................................................... 2


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                                                                            Page
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     2.16     Plan Interest Rate............................................ 2

     2.17     Performance Share............................................. 2

     2.18     TSR or Total Shareholder Return............................... 2

Article 3 - Administration.................................................. 3

     3.1      Committee and Board to Administer............................. 3

     3.2      Authority of the Committee and Board.......................... 3

     3.3      Decisions Binding............................................. 3

Article 4 - Awards.......................................................... 3

     4.1      Eligibility for Awards........................................ 3

Article 5 - Performance Cycle and Performance Comparison.................... 4

     5.1      Performance Cycle............................................. 4

     5.2      Performance Comparison........................................ 4

Article 6 - Grant of Awards................................................. 4

     6.1      Grant of Performance Shares................................... 4

     6.2      Initial Individual Award...................................... 4

     6.3      Initial Grant................................................. 4

     6.4      Adjustment to Initial Grant................................... 5

Article 7 - Dividend Equivalents............................................ 6

     7.1      Dividend Equivalents.......................................... 6

Article 8 - Vesting of Performance Shares................................... 6

     8.1      Vesting Date of Performance Shares - General.................. 6

     8.2      Death, Disability & Retirement - Prior to Vesting Date........ 6


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     8.3      Common Stock Holding Requirement.............................. 6

Article 9 - Valuation and Payment of Final Awards........................... 7

     9.1      Amount of Final Award - General............................... 7

     9.2      Amount of Final Award - Death................................. 7

     9.3      Payment of Final Award - General.............................. 7

     9.4      Payment of Final Award - Death................................ 7

Article 10 - Deferral of Payments........................................... 7

     10.1     Election to Defer............................................. 7

     10.2     Deferral Election Agreement................................... 8

     10.3     Establishment of Deferred Account............................. 8

     10.4     Dividend Equivalents.......................................... 8

     10.5     Timing of Retirement Distributions............................ 8

     10.6     Form of Distributions......................................... 9

     10.7     Termination Benefit........................................... 9

     10.8     Change in Payment Option...................................... 9

     10.9     Hardship Withdrawal Benefits.................................. 9

     10.10    Interaction with the MCN Energy Group Mandatory Deferred
              Compensation Plan............................................. 9

Article 11 - Funding of Benefits............................................ 9

     11.1     Unfunded Plan................................................. 9

     11.2     Non-ERISA Plan................................................ 10

Article 12 - Tax Withholdings............................................... 10

     12.1     Tax Withholding............................................... 10


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Article 13 - Selection of and Payments to a Beneficiary..................... 11

     13.1     Beneficiary Designation....................................... 11

     13.2     Change in Beneficiary Designation............................. 11

     13.3     Pre-Retirement Survivor Benefit  ............................. 11

     13.4     Post-Retirement Survivor Benefit.............................. 11

Article 14 - Amendment and Termination...................................... 11

     14.1     Amendment, Modification, and Termination...................... 11

     14.2     Awards Previously Granted..................................... 12

     14.3     Right to Suspend.............................................. 12

     14.4     Right to Accelerate........................................... 12

Article 15 - Miscellaneous.................................................. 12

     15.1     No Right of Continued Employment.............................. 12

     15.2     Delivery of Shares............................................ 12

     15.3     Transfer and Leave of Absence................................. 12

     15.4     Michigan Law to Govern........................................ 12

     15.5     Forfeitures................................................... 12

     15.6     Gender, Number and Heading ................................... 13

Article 16 - Change in Control.............................................. 13

     16.1     Change in Control............................................. 13

     16.2     Transfer to Rabbi Trust....................................... 14

     16.3     Joint and Several Liability................................... 14

Attachments

Historical Background


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                              MCN ENERGY GROUP INC.
                               LONG-TERM INCENTIVE
                             PERFORMANCE SHARE PLAN

                    (AS AMENDED AND RESTATED OCTOBER 1, 1997)


                                    ARTICLE 1
                        TITLE, PURPOSE AND EFFECTIVE DATE

         1.1  TITLE. The title of the Plan, formerly the "MCN Energy Group
Long-Term Incentive Performance Unit Plan," shall be the "MCN Energy Group
Long-Term Incentive Performance Share Plan" and is referred to in this document
as the "Plan." This Plan is governed by the broader provisions set forth in the
MCN Corporation Stock Incentive Plan approved by shareholders on May 10, 1989.
Any conflicting provisions between such plan and this Plan shall be governed by
the MCN Corporation Stock Incentive Plan.

         1.2  PURPOSE. The purpose of the Plan is to promote the success of MCN
Energy Group Inc. (the "Corporation" or "MCN") by providing financial incentives
to Key Employees of the Corporation and its affiliated companies, thereby
promoting the long-term growth and financial success of the Corporation by (i)
attracting and retaining outstanding ability, (ii) strengthening the
Corporation's capability to develop, maintain, and direct a competent management
team, (iii) providing an effective means for Key Employees to acquire and
maintain ownership of MCN stock, (iv) motivating Key Employees to achieve
long-range performance goals and objectives, and (v) providing incentive
compensation opportunities competitive with those of other major corporations.

         1.3  EFFECTIVE DATE.  The Plan is effective October 1, 1997.


                                    ARTICLE 2
                                   DEFINITIONS

         The following terms have the meaning described below when used in the
Plan:

         2.1  "AFFILIATED COMPANY" means any corporation while such corporation
is a member of the same controlled group of corporations (within the meaning of
Section 414(b) of the Code) as the Corporation or any other employing entity
while such entity is under common control (within the meaning of Section 414(c)
of the Code) of the Corporation.

         2.2  "AWARD" shall mean a grant of Performance Shares under this Plan.

         2.3  "BOARD OF DIRECTORS" or "BOARD" shall mean the Board of Directors 
of the Corporation.



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         2.4  "CAUSE" shall mean repeated material breaches of a Key Employee's
duties of employment which are not cured after receipt by the Key Employee of
written notice specifying such breaches or the Key Employee's conviction of a
felony involving moral turpitude.

         2.5  "CODE" shall mean the Internal Revenue Code of 1986, as amended.

         2.6  "COMMITTEE" shall mean not less than three Nonemployee Directors 
of the Board, who, at the time of service on the Compensation Committee
hereunder, are, and at all times during the twelve month period prior to his or
her becoming a member shall have been, not eligible to receive an Award granted
by such Committee under the Plan.

         2.7  "COMMON STOCK" shall mean common stock, par value $.01 of the
Corporation.

         2.8  "CORPORATION" shall mean MCN Energy Group Inc. or any successor to
it in ownership of all or substantially all of its assets.

         2.9  "DEFERRED ACCOUNT" shall mean an account established for a
Participant under Section 10.3.

         2.10 "DISABILITY" shall have the meaning set forth in Section 22(e)(3)
of the Code.

         2.11 "KEY EMPLOYEE" shall mean an employee of the Corporation who
occupies a responsible executive, professional, or administrative position and
who has the capacity to contribute to the success of the Corporation, as
determined by the Committee or Board.

         2.12 "NONEMPLOYEE DIRECTOR" shall have the meaning ascribed to such
term in Rule 16b-3 of the Securities Exchange Act of 1934.

         2.13 "PARTICIPANT" shall mean a Key Employee who has been granted an
Award.

         2.14 "PARTICIPATING CORPORATION" shall mean the Corporation, Affiliated
Company, or other affiliated entity (whether or not incorporated) designated by
the Board of Directors.

         2.15 "PEER GROUP" shall mean a peer group of 16 comparison companies as
reflected in Attachment I. The list may be revised as and when the Board deems
appropriate.

         2.16 "PLAN INTEREST RATE" shall mean the average interest rate of
10-year U.S. Treasury Notes for the November of the prior calendar year, or such
other rate as set by the Committee or Board.

         2.17 "PERFORMANCE SHARE" shall mean an award granted under Section 6.1.

         2.18 "TSR" OR "TOTAL SHAREHOLDER RETURN" shall mean the percentage
increase in value at the end of a three year period of $100 invested in Common
Stock at the beginning of the 


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period with all dividends being reinvested at the price of Common Stock at the
end of the month in which the dividend is paid. To determine the value at the
beginning and end of any period, a calculation is made of the average Common
Stock price for the trading days from December 17 through January 15.


                                    ARTICLE 3
                                 ADMINISTRATION

         3.1  COMMITTEE AND BOARD TO ADMINISTER. The Committee and Board shall
administer the Plan. A majority of the members of the Committee or Board shall
constitute a quorum for the conduct of business at any meeting. They shall act
by majority vote of the members present at a duly convened meeting, which may
include a meeting by conference telephone call held in accordance with
applicable law. Action may be taken without a meeting if written consent thereto
is given in accordance with applicable law. The Committee or Board may delegate
its authority to administer the Plan.

         3.2  AUTHORITY OF THE COMMITTEE AND BOARD. Except as limited by law or
by the Certificate of Incorporation or Bylaws of the Corporation, and subject to
the provisions herein, the Committee or Board shall have full power to select
employees who shall participate in the Plan; determine the sizes and types of
Awards; determine the terms and conditions of Awards in a manner consistent with
the Plan; construe and interpret the Plan and any agreement or instrument
entered into under the Plan as they apply to employees; establish, amend, or
waive rules and regulations for the Plan's administration as they apply to
employees; and (subject to the provisions of Article 14 herein) amend the terms
and conditions of any outstanding Award to the extent such terms and conditions
are within the discretion of the Committee or Board as provided in the Plan.
Further, they shall make all other determinations, which may be necessary or
advisable for the administration of the Plan, as the Plan applies to employees.
The Committee or Board may delegate its authority as identified herein.

         3.3  DECISIONS BINDING. All determinations and decisions made by the
Committee or Board pursuant to the provisions of the Plan and all related orders
and resolutions of the Board shall be final, conclusive, and binding on all
persons, including the Corporation, its stockholders, Directors, employees,
Participants and their estates and beneficiaries.


                                    ARTICLE 4
                                     AWARDS

         4.1  ELIGIBILITY FOR AWARDS. An Award may be made to a Key Employee
selected by the Committee or Board. In making this selection, and in determining
the amount of the Award, consideration may be given to the functions and
responsibilities of the Key Employee, his present and potential contributions to
the success of the Corporation, the value of his services to the Corporation,
and such other factors deemed relevant.


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                                    ARTICLE 5
                  PERFORMANCE CYCLE AND PERFORMANCE COMPARISON

         5.1  PERFORMANCE CYCLE. The performance cycle is six years. Each
performance cycle is divided into two parts of three years each. Performance
cycles overlap.

         5.2  PERFORMANCE COMPARISON. The performance results for the Peer Group
and MCN shall be arranged on the basis of TSR from highest to lowest. The Peer
Group shall be divided into equal fourths or quartiles, with I being the highest
quartile and IV the lowest.


                                    ARTICLE 6
                                 GRANT OF AWARDS

         6.1  GRANT OF PERFORMANCE SHARES. Subject to the limitations of the MCN
Energy Group Inc. Stock Incentive Plan, the Committee or Board shall, after such
consultation with and consideration of the recommendations of management as the
Committee or Board considers desirable, select those Key Employees to whom
Performance Shares will be granted. The value of Performance Shares shall be
based in whole or in part, on the value of Common Stock. Subject to the
provisions of the Plan, Performance Shares shall be subject to such terms,
restrictions, conditions, vesting requirements, and payment rules (all of which
are sometimes hereinafter collectively referred to as "rules") as the Committee
or Board may determine in its sole discretion. All such rules applicable to a
particular award of Performance Shares shall be reflected in writing and
furnished to the Key Employee at the time of grant. The rules need not be
identical for each award of Performance Shares.

         6.2  INITIAL INDIVIDUAL AWARD. Initial individual Awards will be
established for each Key Employee during the first quarter of the fourth year of
the performance cycle, in accordance with Table I of Attachment II. The major
factors considered in determining the level of an individual award include: (a)
prior contribution and accomplishments; (b) projected contribution and impact on
driving business performance and shareholder value over the next three years;
(c) career potential; and (d) retention.

         6.3  INITIAL GRANT. Subject to the Committee's or the Board's
discretion, the initial grant shall be made in the first quarter of the fourth
year of the performance cycle, based on TSR in the first three years of the
performance cycle as compared to TSR of the Peer Group. Initial grants are
determined by adjusting the initial individual Award either upward or downward
based on MCN's TSR performance compared to the Peer Group, as reflected in Table
II on Attachment II. Other performance criteria may be used at the sole
discretion of the Board or Committee.

         6.4  ADJUSTMENT TO INITIAL GRANT. An adjustment of initial grants may 
be made at the sole discretion of (i) the Board or Committee for a Participant
in Tiers I and II; and (ii) the Chairman of


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MCN for any other Participant. In general, however, an initial grant shall be
adjusted as described below for the circumstances listed in 6.4(a) through (e).

                   (a)  NORMAL RETIREMENT OR DISABILITY. In the event of the
retirement of a Participant at age 62 or older, or retirement due to Disability,
the initial grant will be unchanged unless prorated at the discretion of the
Board or the Chairman of the Board, as appropriate, according to the number of
whole months in the last half of the performance cycle that the Participant was
an active employee. Any proration of initial grants shall be effective as of the
date of retirement. Final awards, if any, will be given at the end of the
performance cycle and adjusted pursuant to Section 9.1.

                   (b)  EARLY RETIREMENT. In the event of the retirement of a
Participant prior to age 62, the initial grant shall be prorated according to
the number of whole months in the last half of the performance cycle that the
Participant was an active employee. Any proration of initial grants shall be
effective as of the date of early retirement. Final awards, if any, will be
given at the end of the performance cycle and adjusted pursuant to Section 9.1.

                   (c)  DEATH. In the event of the death of the Participant, the
initial grant for each performance cycle shall be prorated according to the
number of whole months in the last half of the performance cycle that the
Participant was an active employee. The proration of initial grants shall be
effective as of the date of death and such Award shall vest in accordance with
Section 8.2. The final Award for each performance cycle shall be valued and paid
in accordance with Sections 9.2 and 9.4.

                   (d)  OTHER TERMINATIONS. In the event of termination for any
reason not described in Sections 6.4(a), (b) or (c), a Participant's initial
grants may be adjusted by all, none, or any portion of the initial grants that
have been given to the Participant, in accordance with subsection (e) of this
section 6.4. The reduction in initial grants is effective as of the date of
termination. Final awards, if any, will be given at the end of the performance
cycle and adjusted pursuant to Section 9.1.

                   (e)  FOR PURPOSES OF INITIAL GRANTS ISSUED IN 1994 AND 1995
ONLY. If a Participant voluntarily terminates employment with MCN or a
Participating Corporation:

                        (i)   In the first year of the second part of the
performance cycle (year four), the Participant's initial grant may be reduced to
zero;

                        (ii)  In the second year of the second part of the
performance cycle (year five), the Participant's initial grant may be reduced to
an amount not less than 10 percent of the initial grant; and

                        (iii) In the third year of the second part of the
performance cycle (year six) up through the payment of the final award (in year
seven), the Participant's initial grant may be reduced to an amount not less
than 20 percent of the initial grant.

                   Final awards, if any, will be given at the end of the
performance cycle and adjusted pursuant to Section 9.1.




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                                    ARTICLE 7
                              DIVIDEND EQUIVALENTS

         7.1  DIVIDEND EQUIVALENTS. During the second part of the performance
cycle (years four through six) Participants will receive dividend equivalent
amounts based on the number of Performance Shares in the initial grant, as
adjusted pursuant to Section 6.4. Dividend equivalents for dividends with a
record date that is subsequent to a Participant's retirement or termination
date, will be paid to the Participant based on the reduced number of Performance
Shares, as determined under Section 6.4.


                                    ARTICLE 8
                          VESTING OF PERFORMANCE SHARES

         8.1  VESTING DATE OF PERFORMANCE SHARES - GENERAL. Subject to the
Committee's or the Board's discretion and the rules of Sections 6.4 and 16.1,
Performance Shares shall fully vest and be one hundred percent (100%)
nonforfeitable on the date the Board approves the final Award (the "Vesting
Date").

         8.2  DEATH - PRIOR TO VESTING DATE. Subject to the Committee's or the
Board's discretion and the rules of Sections 6.4 and 16.1, upon termination of
employment prior to the Vesting Date by reason of the Participant's death, all
Performance Shares granted to such Participant shall become fully vested and
nonforfeitable as of the date of death.

         8.3  COMMON STOCK HOLDING REQUIREMENT. Participants receiving Common
Stock as a final award under the Plan are required to hold such Common Stock
until they separate employment from the Company, to the extent the Participant
does not meet the Common Stock Ownership Guidelines described in Attachment III.
         Participants must consult with MCN's Legal Department prior to
executing any sale of Common Stock. Compliance with the Common Stock Ownership
Guidelines will be determined at that time. A Participant's failure to comply
with this section 8.3 shall result in disciplinary action up to and including
termination of employment, at the discretion of the Board or Committee.

                                    ARTICLE 9
                      VALUATION AND PAYMENT OF FINAL AWARDS

         9.1  AMOUNT OF FINAL AWARD - GENERAL. Final Awards will be determined 
by adjusting the initial grant units either upward or downward based on the
Corporation's performance in years four through six of the performance cycle as
compared to the TSR of the Peer Group. Calculation of TSR performance for the
final Award will follow that described in Section 5.2. Other performance
criteria may be used at the sole discretion of the Board or Committee. The Board
will authorize the size of the final Award based on Table III in Attachment II.
The 

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value of the final Award shall be determined using the simple average of the
sales price of the shares of Common Stock, sold under the provisions of this
Plan, over the five trading-day period beginning with the trading day after the
day the MCN Board of Directors approves the final Award.

         9.2  AMOUNT OF FINAL AWARD - DEATH. Final Awards will be determined by
adjusting the initial grant units either upward or downward based on the
midpoint percentage of the Corporation's TSR quartile compared to the TSR of the
Peer Group for the quarter immediately preceding the Participant's date of
death. The value of the final Award shall be determined using the simple average
of the reported high and low prices of Common Stock on the New York Stock
Exchange composite tape on the date of death. If the date of death is not a
trading day, the value of the final Award shall be determined using the simple
average of the reported high and low prices of Common Stock on the New York
Stock Exchange composite tape on the first trading day prior to the date of
death.

         9.3  PAYMENT OF FINAL AWARD - GENERAL. Final Awards, in the form of
Common Stock, will be made in the first quarter following the end of the
six-year performance cycle.

         9.4  PAYMENT OF FINAL AWARD - DEATH. The final Award, in the form of
Common Stock, shall be paid to the Beneficiary no later than 120 days after the
Participant's date of death.


                                   ARTICLE 10
                              DEFERRAL OF PAYMENTS

         10.1 ELECTION TO DEFER. A Participant in Tiers I through V may elect,
  no later than October 31 of the calendar year preceding the calendar year in
  which an Award would otherwise be payable to the Participant, to defer his
  Award in an amount (i) not less than 50 percent, nor (ii) in excess of 100
  percent of the Award less the Federal Insurance Contributions Act tax on such
  Award, in 10 percent increments. The Award shall be deferred until termination
  of employment with the Corporation (the "Deferral Period"). The Deferral
  Period may not extend past the date the Participant terminates employment with
  the Corporation for any reason.

         10.2 DEFERRAL ELECTION AGREEMENT. The Committee or Board shall provide
to each Key Employee a form of Deferral Election Agreement (See Attachment IV),
which shall set forth the Key Employee's acceptance of the terms provided
hereunder, his agreement to be bound by the terms of the Plan, and such other
matters as are set forth in this Plan or deemed advisable by the Committee or
Board. The most recent Deferral Election Agreement shall be effective for all
payments made to a Participant under the Plan with regards to the Deferral
Period, payment of dividend equivalents and distribution elections.

         10.3 ESTABLISHMENT OF DEFERRED ACCOUNT. The Committee or Board shall
establish a Deferred Account for each Participant in regards to the Awards the
Participant has elected to defer, as set forth on his Deferral Election
Agreement.


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                   (a)  DENOMINATION OF DEFERRALS - GENERAL. During the Deferral
Period, a Participant's Deferred Account shall be denominated in common stock
equivalents equal to the number of shares of Common Stock the Participant would
have otherwise received ("Share Equivalents"), had he not made an election to
defer under Section 10.1 A Participant's Deferred Account shall earn dividend
equivalents during the Deferral Period in accordance with Section 10.4.

                   (b)  DENOMINATION OF DEFERRALS -AFTER COMPLETION OF DEFERRAL
PERIOD OR AGE 65. On the earlier of the date (i) the Deferral Period ends or
(ii) the Participant turns age 65 ("Valuation Date"), the Participant's account
shall be valued on a cash basis, using the average of the high and low Common
Stock price on the New York Stock Exchange Composite Tape on the Valuation Date.
Such cash valuation shall be used for purposes of determining the amount of
interest to be credited to the Participant's account during the period annual
distributions are made to the Participant ("Payout Period") and for purposes of
determining the number of shares of Common Stock that will be distributed to a
Participant during the Payout Period, in accordance with Section 10.6. Interest
shall be credited annually on the Anniversary Date on the declining cash balance
at the Plan Interest Rate. The Human Resources Department shall notify each
Participant of his account balance within a reasonable time after the end of the
Participant's Deferral Period.

         10.4 DIVIDEND EQUIVALENTS. Dividend equivalents equal to 50% of the
dividends payable on MCN Common Stock shall be credited to a Participant's
Account during the Deferral Period based on the Share Equivalents held in such
Participant's Account. Dividend equivalents shall be reinvested in Share
Equivalents based upon the average of the high and low Common Stock price on the
dividend payment date. Alternatively, a Participant may elect on his Deferral
Election Agreement to have all of such credited dividend equivalents paid
directly to him in cash during the Plan Year. A Participant's election regarding
dividend equivalents shall be effective for all Share Equivalents held in the
Participant's Account on the January 1 immediately following execution of his
Deferral Election Form and shall remain in effect until revoked by the
Participant. Revocation of a dividend equivalent election shall be effective on
the January 1 immediately following revocation.

         10.5 TIMING OF RETIREMENT DISTRIBUTIONS. Upon completion of a
Participant's Deferral Period, the distribution of the Participant's Deferred
Account shall be made in accordance with the Participant's selection on his
Deferral Form; either (i) in annual payments over a period not less than one
year and not more than 15 years, in one year increments, or (ii) as a lump sum
distribution. If no Deferral Form is on file or no distribution option is
indicated on the Deferral Form, the Participant's Deferred Account shall be
distributed in one lump sum. All distributions shall be paid out at the end of
the quarter in which the Participant's retirement date occurs. If a Participant
has elected annual payments, the initial payment shall be made at the end of the
quarter in which the Participant's Deferral Period ends. All subsequent annual
payments shall be made at the end of the quarter in which the anniversary of the
Participant's Deferral Period ("Anniversary Date") occurs. Interest shall accrue
on the value of the Participant's account from the Valuation date to the end of
the quarter in which the initial payment is distributed.


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<PAGE>   14


         10.6 FORM OF DISTRIBUTIONS. Notwithstanding the fact that a
Participant's Deferred Account shall be valued on a cash basis as of the
Valuation Date, the distribution to a Participant shall be paid in MCN common
stock. The number of shares of Common Stock to be distributed shall equal the
number of shares (rounded up to the next whole number of shares) such
cash-valued Deferred Account, divided by the number of payments remaining in the
Payout Period, could have purchased based on the average of the high and low
Common Stock price on the New York Stock Exchange Composite Tape on the fifth
trading-day prior to the end of the quarter in which Valuation Date (or
Anniversary Date for all subsequent payments) occurs. The number of shares
distributed annually shall be determined by amortizing the cash value of the
Participant's Deferred Account over the Payout Period. Interest shall be
credited annually on the declining balance at the Plan Interest Rate. The number
of shares distributed annually to the Participant shall be recalculated on the
Participant's Anniversary Date to reflect changes in the Plan Interest Rate, the
decrease in the number of annual payments left to be made, and other changes to
the Participant's Deferred Account balance. The amortization schedule shall be
updated annually to reflect the average 10-year Treasury Note interest rate for
the fifth trading-day prior to the end of the quarter in which Valuation Date
(or Anniversary Date for all subsequent payments) in which the distribution is
to be made.

         10.7 TERMINATION BENEFIT. A Participant who terminates employment prior
to completion of his Deferral Period shall receive payment of his Account
balance in accordance with the Participant's election on his Deferral Election
Agreement; either in annual payments over three years or as a lump sum
distribution. If no election is indicated on the Participant's Deferral Election
Agreement, the Participant's termination benefit shall be paid to him in annual
payments over three years beginning no later than 120 days after termination of
employment. If the Participant's account is to be paid in annual installments,
the account shall be valued in accordance with Section 10.3(b), using the
termination date as the Valuation Date, and the timing and form of payments
shall be determined in accordance with Sections 10.5 and 10.6.

         10.8 CHANGE IN PAYMENT OPTION. A Participant's election regarding the
distribution of his account on his Deferral Election Agreement shall be
effective for all distributions from the Participant's account on the January 1
immediately following execution of his Deferral Election Form and shall remain
in effect until a different election is indicated by the Participant on a
subsequent Deferral Election Form. The payment options selected by the
Participant on his Deferral Election Agreement may be changed at any time by the
Participant submitting a new payment selection to the Committee or Board, but a
change shall be effective only if it is received by the Committee or Board at
least 12 months before payments under the Plan commence.

         10.9 HARDSHIP WITHDRAWAL BENEFITS. At any time prior to a distribution
in accordance with Section 10.6, a Participant may request that the Committee or
Board make a distribution to him of all or part of his Deferred Account within
120 days. Such distribution shall be made only if the Committee or Board
determines that the Participant is suffering from a financial hardship that
cannot be satisfied from his normal sources of income, and the distribution
shall be limited to the amount required to meet the financial hardship. In
making these determinations, the Committee or Board shall utilize the
regulations proposed or adopted by the U.S. Department of Treasury pursuant to
Section 401(k) of the Code and the rules under the Savings Plan. A financial
hardship shall first be satisfied 


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from (i) a loan under the provisions of the Savings Plan, (ii) the MCN Executive
Deferred Compensation Plan, and (iii) the Supplemental Savings Plan, before a
hardship distribution may be made from the Plan.

         10.10 INTERACTION WITH THE MCN ENERGY GROUP MANDATORY DEFERRED
COMPENSATION PLAN. The portion of any Award required to be deferred under The
MCN Energy Group Mandatory Deferred Compensation Plan will be deemed to be
deferred in accordance with Section 10.1 of the Plan.


                                   ARTICLE 11
                               FUNDING OF BENEFITS

         11.1  UNFUNDED PLAN. The Plan shall be unfunded. All benefits payable
under the Plan shall be paid from the Corporation's general assets. The
Corporation shall not be required to set aside or hold in trust any funds for
the benefit of a Participant or Beneficiary, who shall have the status of a
general unsecured creditor with respect to the Corporation's obligation to make
benefit payments pursuant to the Plan. Any assets of the Corporation available
to pay Plan benefits shall be subject to the claims of the Corporation's general
creditors and may be used by the Corporation in its sole discretion for any
purpose. No employee shall have voting or other rights with respect to such
shares of Common Stock prior to the delivery of such shares. The Corporation
shall not, by any provisions of the Plan, be deemed to be a trustee of any
Common Stock or any other property under the Plan, and any liabilities of the
Corporation to any employee pursuant to the Plan shall be those of a debtor
pursuant to such contract obligations as are created by or pursuant to the Plan,
and the rights of any employee, former employee, or beneficiary under the Plan
shall be limited to those of a general creditor of the Corporation. In its sole
discretion, the Board may authorize the creation of trusts or other arrangements
to meet the obligations of the Corporation and each other Participating
Corporation under the Plan provided, however, that the existence of such trusts
or other arrangements is consistent with the unfunded status of the Plan.

         11.2  NON-ERISA PLAN. The Plan is intended to provide benefits for "a
select group of management or highly compensated employees" within the meaning
of Sections 201, 301 and 401 of the Employee Retirement Income Security Act of
1974, as amended ("ERISA"), and therefore to be exempt from Sections 2, 3 and 4
of Title 1 of ERISA. Accordingly, the Plan shall terminate and, existing account
balances and other benefits in pay status shall be paid in a single, actuarially
equivalent lump-sum and no further benefits, vested or non-vested, shall be paid
hereunder in the event it is determined by a court of competent jurisdiction or
by an opinion of counsel that the Plan constitutes an employee pension benefit
plan within the meaning of Section 3(2) of ERISA which is not so exempt.




                                   ARTICLE 12
                                TAX WITHHOLDINGS

                                       10
<PAGE>   16

         12.1 TAX WITHHOLDING. The Corporation shall not make the delivery of
any shares of Common Stock until the Participant has made satisfactory
arrangements for the payment of any applicable withholding taxes. The
tax-withholding obligation may be satisfied by any of the following means, a
combination of such means, or any other means established by the Committee or
Board:
              (a)  tendering cash payment;

              (b)  authorizing the Corporation to (i) withhold 50% of the Common
Stock to be issued and (ii) facilitate the sale of such stock; or 

              (c)  delivery to the Corporation by the Participant of owned and
unencumbered shares of Common Stock having an aggregate fair market value on the
date the withholding tax arises less than or equal to the amount of the
withholding tax obligation.

The Participant must satisfy the tax-withholding obligation no later than 30
days from the date the Award vests. The Committee or Board may establish
procedures it deems appropriate to assist a Participant in making such payment.


                                   ARTICLE 13
                   SELECTION OF AND PAYMENTS TO A BENEFICIARY

         13.1 BENEFICIARY DESIGNATION. A Participant shall designate a
beneficiary on his Beneficiary Designation Form, as provided in Attachment V.
The designation of a beneficiary other than the Participant's spouse must be
consented to in writing by the spouse. If a Participant has not designated a
beneficiary, or if a designated beneficiary is not living or in existence at the
time of a Participant's death, any death benefits payable under the Plan shall
be paid to the Participant's spouse, if then living, and if the Participant's
spouse is not then living, to the Participant's estate.

         13.2 CHANGE IN BENEFICIARY DESIGNATION. A Participant may change
the designated beneficiary, subject to the restriction in Section 13.1, from
time to time by filing a new written designation with the Committee or Board.
Such designation shall be effective upon receipt by the Committee or Board.

         13.3 PRE-RETIREMENT SURVIVOR BENEFIT. If a Participant dies prior to
completion of the Deferral Period, his Beneficiary shall be entitled to receive
a distribution of the Participant's Deferred Account. The distribution to a
beneficiary shall be paid in Common Stock equal to the number of shares of
Common Stock deemed to be held in the Participant's Deferred Account and valued
at the closing price of MCN Common Stock on the New York Stock Exchange
composite tape on the day of the Participant's death. The distribution shall be
paid in accordance with the Participant's selection on his Deferral Form; either
in annual installments over a three-year period, or as a lump sum distribution.
If the Participant's account is to be paid in annual installments, the account
shall be valued in accordance with Section 10.3(b), using the Participant's date
of death as the Valuation Date, and the timing and form of payments shall be
determined in accordance with Sections 10.5 and 10.6. Payments


                                       11
<PAGE>   17

to the beneficiary shall begin as soon as practicable, but in no event later
than one year following the Participant's death.

         13.4 POST-RETIREMENT SURVIVOR BENEFIT. If a Participant dies subsequent
to the start of his distribution payments under Section 10.5, his beneficiary
shall be entitled to continue to receive the distribution of the Participant's
Deferred Account for the remainder of the period over which benefits were being
paid to the deceased Participant.



                                   ARTICLE 14
                            AMENDMENT AND TERMINATION

         14.1 AMENDMENT, MODIFICATION, AND TERMINATION. The Committee or Board
may at any time and from time to time, alter, amend, suspend, or terminate the
Plan in whole or in part; provided, however, that no amendment which requires
shareholder approval in order for the Plan to continue to comply with Rule 16b-3
under the Securities Exchange Act of 1934, including any successor to such Rule,
shall be effective unless such amendment shall be approved by the requisite vote
of shareholders of the Corporation entitled to vote thereon.

         14.2 AWARDS PREVIOUSLY GRANTED. No termination, amendment, or
modification of the Plan shall adversely affect in any material way any Award
previously granted under the Plan, without the written consent of the
Participant holding such Award.

         14.3 RIGHT TO SUSPEND. If the Board determines that payments under
Sections 7.1, 9.3, 9.4 or 10.5 of the Plan would have a materially adverse
affect on the Company's ability to carry on its business, the Board may suspend
any or all such payments temporarily for such time as in it sole discretion it
deems advisable, but in no event for a period in excess of one year. The Company
shall pay such suspended payments in a lump sum distribution of (i) Common Stock
for payments under Sections 9.3, 9.4 and 10.6, and (ii) cash for payments under
Section 7.1, immediately upon the expiration of the period of suspension.

         14.4 RIGHT TO ACCELERATE. The Board in its sole discretion may
accelerate all vested benefits upon termination of the Plan, and pay such
benefits in a single, actuarially equivalent lump-sum distribution of Common
Stock.


                                   ARTICLE 15
                                  MISCELLANEOUS

         15.1 NO RIGHT OF CONTINUED EMPLOYMENT. Neither the establishment of the
Plan, the granting of an Award, or the payment of any benefits hereunder or any
action of the Corporation or of the Board or of the Committee shall be held or
construed to confer upon any person any legal right to be continued in the
employ of the Corporation or its direct or indirect subsidiaries, 



                                       12
<PAGE>   18

each of which expressly reserves the right to discharge any employee whenever
the interest of any such Corporation in its sole discretion may so require
without liability to such Corporation, the Board or the Committee except as to
any rights which may be expressly conferred upon such employee under the Plan.

         15.2 DELIVERY OF SHARES. No shares shall be delivered pursuant to the
payment of any Award unless the requirements of such laws and regulations, as
may be deemed by the Committee or Board to be applicable thereto, are satisfied.

         15.3 TRANSFER AND LEAVE OF ABSENCE. A transfer of a Key Employee from a
Participating Corporation to an Affiliated Company and a leave of absence duly
authorized in writing by the Participating Corporation, for military service or
sickness, or for any other purpose approved by the Participating Corporation,
shall not be deemed a termination of employment.

         15.4 MICHIGAN LAW TO GOVERN. All questions pertaining to the
construction, regulation, validity, and effect of the provisions of the Plan
shall be determined in accordance with the laws of the State of Michigan.

         15.5 FORFEITURES. Notwithstanding any other provisions of this Plan, if
the Committee or Board finds by a majority vote, after full consideration of the
facts, that a Participant, before or after termination of his employment with
the Corporation or an Affiliated Company for any reason:

              (a)  committed or engaged in fraud, embezzlement, theft,
commission of a felony, or proven dishonesty in the course of his employment by
the Corporation or its subsidiaries, which conduct damaged the Corporation or
its subsidiaries, or disclosed trade secrets of the Corporation or its
subsidiaries;

              (b)  participated, engaged in, or had a financial or other
interest, whether as an employee, officer, director, consultant, contractor,
shareholder, owner, or otherwise, in any commercial endeavor in the United
States which has a significant competitive impact on the business of the
Corporation or its subsidiaries without the written consent of the Corporation
or its subsidiaries; or

              (c)  has taken any other action that has a significant adverse
impact in the Corporation or its subsidiaries,

the Participant shall forfeit all outstanding Awards, which are not vested. This
forfeiture requirement shall not apply to Awards that have been deferred under
Article 10. Clause (b) shall not be deemed to have been violated solely by
reason of the Participant's ownership of stock or securities of any publicly
owned corporation, if that ownership does not result in effective control of the
Corporation.

              The decision of the Committee or Board as to the cause of the
Participant's discharge, the damage done to the Corporation or its subsidiaries,
and the extent of the 


                                       13
<PAGE>   19

Participant's competitive activity shall be final. No decision of the Committee
or Board, however, shall affect the finality of the discharge of the Participant
by the Corporation or its subsidiaries in any manner.

         15.6 GENDER, NUMBER AND HEADING. Whenever any words are used herein in
the masculine gender, they shall be construed as though they were also used in
the feminine gender in all cases where they would so apply. Whenever any words
used herein are in the singular form, they shall be construed as though they
were also used in the plural form in all cases where they would so apply.
Headings of sections and subsections as used herein are inserted solely for
convenience and reference and constitute no part of the Plan.


                                   ARTICLE 16
                                CHANGE IN CONTROL

         16.1 CHANGE IN CONTROL. In the case of a Change in Control (as defined
in the MCN Energy Group Inc. Stock Incentive Plan), each Performance Share shall
immediately be fully vested and any restrictions on the transfer of previously
issued stock shall lapse. For this purpose, the number of Performance Shares
which shall vest shall in no event be less than one hundred percent (100%) of
the initial grant; provided, however, that for each outstanding award year, if
the Corporation is ranked in the first or second quartile of the peer group
during the second half of the performance cycle at the time of the Change in
Control, the number of Performance Shares which shall vest shall be two hundred
percent (200%) or one hundred fifty percent (150%), respectively, of the initial
grant. Such Award and all performance shares previously deferred shall be paid
within thirty (30) days of such Change in Control, either in shares of Common
Stock or if the Corporation no longer has common stock outstanding, the same
consideration received by the Corporation's shareholders upon the consummation
of the Change in Control transaction.

         16.2 TRANSFER TO RABBI TRUST. The Corporation has established a trust
pursuant to a Trust Agreement dated January 3, 1991 (the "Rabbi Trust"). The
terms of the Rabbi Trust provide that, in the event of a Change of Control and
thereafter, assets are to be transferred to such Rabbi Trust to provide benefits
under the Plan. The Corporation shall make all transfers of funds required by
the Rabbi Trust in a timely manner and shall otherwise abide by the terms of the
Rabbi Trust. The transfer of funds required by this section shall be made in
shares of Common Stock.

         16.3 JOINT AND SEVERAL LIABILITY. Upon and at all times after a Change
in Control, the liability under the Plan of the Corporation and each Affiliated
Company that has adopted the Plan shall be joint and several so that the
Corporation and each such Affiliated Company shall each be liable for all
obligations under the Plan to each employee covered by the Plan, regardless of
the corporation by which such employee is employed.



                                       14
<PAGE>   20

              IN WITNESS WHEREOF, the undersigned officer of the Corporation has
executed this Plan as of this 1st day of October, 1997, pursuant to the
resolution adopted by the Board of Directors of the Corporation.



                                        MCN ENERGY GROUP INC.

                                        BY:
                                           --------------------------

                                        Alfred R. Glancy III
                                        Chairman and Chief Executive Officer


                                        Dated as of                 , 1998
                                                    ----------------

      Effective October 1, 1997



 
                                       15
<PAGE>   21

                                                                    ATTACHMENT I



                             MCN ENERGY GROUP, INC.

                              COMPARISON COMPANIES

Due to MCN's continued transition from a utility holding company to a
diversified energy holding company, a change in the companies making up the peer
group for measuring Performance Share values and payouts was made beginning with
the 1996 plan year.

<TABLE>
<CAPTION>

           PEER GROUP A                                             PEER GROUP B
           ------------                                             ------------
<S>                                                      <C>                        
 1.   Atlanta Gas Light Company                          1.   CMS Energy Corporation
 2.   CMS Energy Corporation                             2.   Coastal Corporation
 3.   Columbia Gas System, Inc.                          3.   Columbia Gas System, Inc.
 4.   Consolidated Natural Gas Company                   4.   Consolidated Natural Gas Company
 5.   DTE Energy Company (Detroit Edison)                5.   Enron Corporation
 6.   Equitable Resources, Inc.                          6.   Equitable Resources, Inc.
 7.   Laclede Gas Company                                7.   K N Energy, Inc.
 8.   Marketspan Corporation (Brooklyn Union)            8.   Marketspan Corporation (Brooklyn Union)
 9.   MCN Energy Group Inc.                              9.   MCN Energy Group Inc.
10.   National Fuel Gas Company                         10.   National Fuel Gas Company
11.   NICOR Inc.                                        11.   ONEOK Inc.
12.   ONEOK Inc.                                        12.   Questar Corporation
13.   Peoples Energy Corporation                        13.   Sonat Inc.
14.   Southwest Gas Corporation                         14.   Southwest Energy Company
15.   Washington Gas Light Company                      15.   The Williams Companies
16.   WICOR, Inc.                                       16.   WICOR, Inc.
</TABLE>



<TABLE>
<CAPTION>

                 APPLICATION OF PEER GROUP TO PERFORMANCE CYCLES

    INITIAL GRANTS                                     FINAL AWARDS           
    --------------                                     ------------           
Period          Year    Peer Group            Period          Year    Peer Group
------          ----    ----------            ------          ----    ----------
<S>             <C>        <C>                <C>             <C>         <C>
1992 - 1994     1995        A                 1995 - 1997     1998        A
1993 - 1995     1996       A/B                1996 - 1998     1999        B
1994 - 1996     1997        B                 1997 - 1999     2000        B
</TABLE>


<PAGE>   22
                                                                   ATTACHMENT II

<TABLE>
<CAPTION>

         TABLE I - INITIAL INDIVIDUAL AWARD - 1997

=======================================================================================================
                                  MCN              MICHCON             MCNIC*            CITIZEN'S
TIER   DESCRIPTION              TARGET %           TARGET %           TARGET %            TARGET % 
                               BASE SALARY       BASE SALARY         BASE SALARY        BASE SALARY
                                                                       
=======================================================================================================
<S>    <C>                     <C>                <C>                <C>                <C>         
I      Chairman & CEO              85%               N/A                 N/A                N/A
-------------------------------------------------------------------------------------------------------
II     Vice Chairman/Pres       50 - 70%           45 - 60%           50 - 70%              N/A
-------------------------------------------------------------------------------------------------------
III    VP/Officer/Exec.         25 - 35%           25 - 35%           25 - 40%           25 - 35%
       Dir.
-------------------------------------------------------------------------------------------------------
IV     Director                 15 - 25%           15 - 25%           15 - 30%           15 - 30%
-------------------------------------------------------------------------------------------------------
V      Sr. Staff/Mgmt.           5 - 15%           5 - 15%             5 - 15%            5 - 15%
-------------------------------------------------------------------------------------------------------
VI     Discretionary            Up to 20%         Up to 20%           Up to 20%          Up to 20%
&                              Population         Population         Population         Population
VII
                               Max. 5% of         Max. 5% of          Max. 5% of         Max. 5% of 
                                 Salary             Salary              Salary             Salary
=======================================================================================================
</TABLE>


*   Includes Mobile Bay Gathering Company and Reed Holdings.

<TABLE>
<CAPTION>

         TABLE II - INITIAL GRANT - 1997

===================================================================================================
                                          INITIAL GRANT
===================================================================================================
                                                                    % OF INITIAL
                  PEER RANKING                                   INDIVIDUAL AWARDS
===================================================================================================
                  <S>                                                <C>
                  1st Quartile                                       125 - 200%
                  2nd Quartile                                        75 - 150%
                  3rd Quartile                                        25 - 100%
                  4th Quartile                                         0 - 50%
===================================================================================================
</TABLE>


<TABLE>
<CAPTION>


         TABLE III - FINAL AWARD - 1997

===================================================================================================
                                           FINAL AWARD
===================================================================================================
                                                                        % OF
                  PEER RANKING                                     INITIAL GRANT
===================================================================================================
                  <S>                                                <C>
                  1st Quartile                                       125 - 200%
                  2nd Quartile                                        75 - 150%
                  3rd Quartile                                        25 - 100%
                  4th Quartile                                         0 - 50%
===================================================================================================
</TABLE>




                                       2
<PAGE>   23

                                                                   ATTACHMENT II


<TABLE>
<CAPTION>

    TABLE I - INITIAL INDIVIDUAL AWARD - 1998

=======================================================================================================
                             MCN              MICHCON             MCNIC*            CITIZEN'S
TIER   DESCRIPTION          TARGET %          TARGET %           TARGET %            TARGET % 
                          BASE SALARY       BASE SALARY         BASE SALARY        BASE SALARY
                                                                  
=======================================================================================================
 <S>   <C>                     <C>                <C>                <C>                <C>      
 I     Chairman & CEO             160%               N/A                 N/A                N/A
-------------------------------------------------------------------------------------------------------
 II    Vice Chairman/Pres      100 - 120%          70 - 95%          110 - 130%             N/A
-------------------------------------------------------------------------------------------------------
 III   VP/Officer/Exec.         45 - 55%           35 - 45%           55 - 65%           30 - 40%
       Dir.
-------------------------------------------------------------------------------------------------------
 IV    Director                 25 - 35%           25 - 35%           30 - 40%           20 - 30%
-------------------------------------------------------------------------------------------------------
 V     Sr. Staff/Mgmt.          15 - 25%           15 - 25%           15 - 25%           10 - 20%
-------------------------------------------------------------------------------------------------------
 VI    Discretionary            Up to 20%         Up to 20%           Up to 20%          Up to 20%
 &                             Population         Population         Population         Population
 VII
                               Max. 5% of         Max. 5% of         Max. 5% of         Max. 5% of 
                                 Salary             Salary             Salary             Salary
=======================================================================================================
</TABLE>

*   Includes Mobile Bay Gathering Company and Reed Holdings.


<TABLE>
<CAPTION>

         TABLE II - INITIAL GRANT - 1998

===================================================================================================
                                          INITIAL GRANT
===================================================================================================
                                                                    % OF INITIAL
                  PEER RANKING                                   INDIVIDUAL AWARDS
===================================================================================================
                  <S>                                                <C>
                  1st Quartile                                       125 - 200%
                  2nd Quartile                                        75 - 150%
                  3rd Quartile                                        25 - 100%
                  4th Quartile                                         0 - 50%
===================================================================================================
</TABLE>


<TABLE>
<CAPTION>

         TABLE III - FINAL AWARD - 1998

===================================================================================================
                                           FINAL AWARD
===================================================================================================
                                                                        % OF
                  PEER RANKING                                     INITIAL GRANT
===================================================================================================
                  <S>                                                <C>
                  1st Quartile                                       125 - 200%
                  2nd Quartile                                        75 - 150%
                  3rd Quartile                                        25 - 100%
                  4th Quartile                                         0 - 50%
===================================================================================================
</TABLE>


<PAGE>   24


                                                                  ATTACHMENT III






                              MCN ENERGY GROUP INC.
                               LONG-TERM INCENTIVE
                             PERFORMANCE SHARE PLAN

                        COMMON STOCK OWNERSHIP GUIDELINES



           -------------------------------------------------------  
           TIER                             GUIDELINE               
           -------------------------------------------------------  
           I                                8 times salary          
           -------------------------------------------------------  
           II                               5 times salary          
           -------------------------------------------------------  
           III                              3 times salary          
           -------------------------------------------------------  
           IV and V                         1 times salary          
           -------------------------------------------------------  
           VI and VII                       None                    
           -------------------------------------------------------  
           


For purposes of meeting these guidelines, the following shares of Common Stock
are included:


-   Actual shares owned outright

-   Shares held in the MCN Energy Group Savings and Stock Ownership Plan

-   Share equivalents in deferral plans

-   Unvested Performance Shares


For purposes of determining when shares received from the Plan may be sold,
unvested Performance Shares are excluded.



<PAGE>   25

                                                                   ATTACHMENT IV

                 MCN ENERGY GROUP INC. LONG-TERM INCENTIVE PLAN
                            PERFORMANCE SHARE PROGRAM
                             DEFERRAL ELECTION FORM

================================================================================

This Benefit Agreement is entered into between                     (the
"Company") and                   , (the "Employee"), pursuant to the MCN Energy
Group Inc. Long-Term Incentive Plan (the "Plan"), with an Effective Date
of                             .

================================================================================
ELECTION TO PARTICIPATE

By the execution of this Benefit Agreement, the Employee hereby elects to
participate in the Plan, and understands and agrees to the following:

I.   Deferrals must be stated as a percentage of the Final Award to be received,
     with a minimum deferral of 50% of the Final Award.

II.  Up to 100% of the Final Award is eligible for deferral, less applicable 
     FICA tax on the Final Award.

III. The Deferral Period remains in effect until termination of employment. 

IV.  The most recent Deferral Period and Distribution election shall be 
     effective for all amounts payable to the Employee under the Plan. 

V.   All Deferral elections are irrevocable and can be modified only in 
     accordance with the Plan.

     I ELECT TO DEFER    % OF THE MCN ENERGY GROUP INC. COMMON STOCK I WILL
     RECEIVE AS A FINAL AWARD OF THE PERFORMANCE SHARES INITIALLY GRANTED TO ME
     ON                          . I UNDERSTAND THAT MY DEFERRAL PERIOD FOR ALL
     SHARE EQUIVALENTS HELD FOR ME UNDER THE PLAN SHALL REMAIN IN EFFECT UNTIL
     MY TERMINATION OF EMPLOYMENT WITH THE COMPANY.

================================================================================
DIVIDEND EQUIVALENT PAYMENT ELECTION

I elect to have the dividend equivalents (equal to 50% of the MCN Energy Group
Inc. common stock dividend rate) from my deferral account shares:

     [ ]   Paid to me in cash; or
     [ ]   Reinvested in my deferral account.


================================================================================
DISTRIBUTION ELECTIONS (PLEASE MAKE ONE (1) ELECTION PER BENEFIT CATEGORY)

A.   Pre-Retirement Survivor Benefits:
     [ ]   Single Lump Sum Payment; OR
     [ ]   Annual Installments Over a Three (3) Year Period

B.   Normal Retirement Benefits:
     [ ]   Single Lump Sum Payment; OR
     [ ]   Annual Installments Over a      Year Period (not to exceed 15 years)
   
C.   Termination Prior To Retirement:
     [ ]   Single Lump Sum Payment; OR
     [ ]   Annual Installments Over a Three (3) Year Period

NOTE: A Post-Retirement Survivor Benefit will continue payments which have
commenced under any of the Installment Payout Options until the full payment
period is satisfied.
================================================================================
ACCEPTANCE OF PLAN TERMS AND BENEFITS

The Employee hereby agrees to all of the terms and conditions of the Plan as set
forth in the Plan document. Participation in the Plan indicates the Employee's
acceptance on his/her own behalf and on the behalf of his/her designated
Beneficiary of the terms of entitlement to all Plan benefits whether payable to
the Employee or his/her survivor. The Employee further understands that no
assets of the Company are to be segregated to pay benefits under the Plan. No
officer, employee, or representative of the Company is authorized to vary such
terms and conditions verbally or in writing. The Plan may be modified only by an
amendment to the Plan adopted by the Committee or the Board of Directors. The
employee understands that a distribution election other than a lump sum will
result in a distribution of a set dollar amount, plus interest, and not a set
number of shares of Common Stock.


----------            ---------------------           --------------------------
Date                  Print Employee's Name           Employee's Signature


<PAGE>   26


                                                                    ATTACHMENT V
================================================================================
                              MCN ENERGY GROUP INC.
                   LONG-TERM INCENTIVE PERFORMANCE SHARE PLAN
                          BENEFICIARY DESIGNATION FORM
================================================================================


---------------------------         -----------------------    -----------------
Employee Name (Please Print)        Social Security Number     Employee I.D.#


     DESIGNATION OF BENEFICIARY

     The Plan provides certain death benefits to the Employee's designated
     Beneficiary. You may change your beneficiary designation at any time by
     executing a new Beneficiary Designation Form. Beneficiary Designation Forms
     are available through the Plan Committee.

     I hereby designate the following Beneficiary, in the event of my death, for
     any and all survivor benefits payable under the MCN Energy Group Inc.
     Long-Term Incentive Performance Share Plan:

     Primary Beneficiary:
                         -------------------------------------------------------

     Relationship to Employee:                        Address: 
                              --------------------        ----------------------

                                                          ----------------------

     Contingent Beneficiary:
                            ----------------------------------------------------

     Relationship to Employee:                       Address:
                              --------------------        ----------------------

                                                          ----------------------

In the event none of the above-named beneficiaries survive me, any unpaid
amounts shall be paid to my lawful successor in interest. I reserve the right to
change this beneficiary designation at any time by filing with the Committee or
its designee a new Beneficiary Designation Form. I understand that my most
recent election as to the beneficiary designation will apply to all award
amounts payable to me at any time.

----------                             --------------------------
Date                                   Employee's Signature



================================================================================
     SPOUSAL CONSENT (REQUIRED FOR ALL NON-SPOUSAL PRIMARY BENEFICIARY 
     DESIGNATIONS)

     I hereby consent to the above election of Beneficiary by my spouse for
     survivor benefits payable under the MCN Energy Group Inc. Long-Term
     Incentive Performance Share Plan. Further, I hereby acknowledge that I
     understand (1) that the effect of my consent may be to forfeit benefits I
     would be entitled to receive upon my spouse's death; (2) that my spouse's
     designation is not valid unless I consent to it; and (3) that my consent is
     irrevocable unless my spouse revokes the designation above.

     ----------      ------------------------         --------------------------
     Date            Print Spouse's Name              Spouse's Signature

================================================================================


<PAGE>   27



                              MCN ENERGY GROUP INC.
                               LONG-TERM INCENTIVE
                             PERFORMANCE SHARE PLAN

                              Historical Background


      2/25/93 Plan adopted.

      5/23/96 Plan amended and restated.

      10/1/97 Plan amended and restated