A control method for optimizing a fleet of generating assets in which groupings of the generating assets comprise remotely located power blocks (860,902) that operate so to collectively generate a fleet output level for a market, wherein the fleet comprises multiple possible generating configurations, the method including the steps of: receiving real-time and historical measured values of operating parameters related to an operation of each generating asset, the measured values of the operating parameters including process inputs and process outputs; for each of the generating assets, deriving a relational expression between the measured values of the process inputs and the measured values of the process outputs; defining a selected operating period, the selected operating period representing a prospective operating period for the fleet; selecting competing operating modes for the fleet for the selected operating period, wherein each competing operating mode defines an unique one of the possible generating configurations of the fleet; based on the relational expressions and the generating configuration for each of the competing operating modes, calculating a result set for the operation of the fleet proposed during the selected operating period; defining a cost function; and evaluating each of the result sets pursuant to the cost function and, based thereupon, designating at least one of the competing operating modes as an optimized operating mode; wherein the optimized operating mode comprises a power sharing recommendation between the power blocks (860,902) of the fleet for generating the fleet output level; wherein the relational expressions collectively comprise a fleet model in which an asset model correlates the measured values for the process input to the process outputs for each of the generating assets characterized by the following steps: wherein, for each of the competing operating modes, the step of calculating the result set for the operation of the fleet proposed during the selected operating period includes a simulation run inclusive of the following steps: defining a proposed parameter set for the competing operating mode; simulating with the fleet model the operation of the fleet over the selected operating period pursuant to the proposed parameter set; and determining the result set from an output of the simulation; wherein the power sharing recommendation comprises a block apportionment schedule dividing the fleet output level between the power blocks (860,902). receiving real-time and historical measured values of operating parameters related to an operation of each generating asset, the measured values of the operating parameters including process inputs and process outputs; for each of the generating assets, deriving a relational expression between the measured values of the process inputs and the measured values of the process outputs; defining a selected operating period, the selected operating period representing a prospective operating period for the fleet; selecting competing operating modes for the fleet for the selected operating period, wherein each competing operating mode defines an unique one of the possible generating configurations of the fleet; based on the relational expressions and the generating configuration for each of the competing operating modes, calculating a result set for the operation of the fleet proposed during the selected operating period; defining a cost function; and evaluating each of the result sets pursuant to the cost function and, based thereupon, designating at least one of the competing operating modes as an optimized operating mode; wherein the optimized operating mode comprises a power sharing recommendation between the power blocks (860,902) of the fleet for generating the fleet output level; wherein the relational expressions collectively comprise a fleet model in which an asset model correlates the measured values for the process input to the process outputs for each of the generating assets characterized by the following steps: wherein, for each of the competing operating modes, the step of calculating the result set for the operation of the fleet proposed during the selected operating period includes a simulation run inclusive of the following steps: defining a proposed parameter set for the competing operating mode; simulating with the fleet model the operation of the fleet over the selected operating period pursuant to the proposed parameter set; and determining the result set from an output of the simulation; wherein the power sharing recommendation comprises a block apportionment schedule dividing the fleet output level between the power blocks (860,902). defining a proposed parameter set for the competing operating mode; simulating with the fleet model the operation of the fleet over the selected operating period pursuant to the proposed parameter set; and determining the result set from an output of the simulation; wherein the power sharing recommendation comprises a block apportionment schedule dividing the fleet output level between the power blocks (860,902).