The Old Adage...
Runway behind you and fuel in the bowzer is no good to you. Also, with the ability to operate with 'De-rated' engines and utilizing Assumed Temperature calculations together, is looking for trouble. It doesn't matter if the performance fits.
There seems to be a missing element in the pilot group today and that's called:
AIRMANSHIP
As Commander and even as a good assertive CRM savvy Co-Pilot, the responsibility for the conduct of a safe flight rests in your hands. Forget what the company wants you to do. The beginning of the operations manual Part A, (if written correctly) tells the reader that the Commander has the sole responsibility for the safe operation of his/her aircraft.