 Negotiated rates-unaccompanied by a change in service conditions that provides cost justification-are a problematical approach to introducing additional flexibility into Postal Service business practices.
Negotiated rates encourage flexibility in the Postal Service but the cost justifications are hard to ignore.
mnli hypothesis: Negotiated rates encourage flexibility in the Postal Service but the cost justifications are hard to ignore. premise:  Negotiated rates-unaccompanied by a change in service conditions that provides cost justification-are a problematical approach to introducing additional flexibility into Postal Service business practices.