So far it sounds like Cosmo Kramer, Latetonite, and DeFacto are all chosing B - don't exceed MMO.
In other checklists, Boeing specifically say, "DO NOT EXCEED . . ." Gear extend limit, leading edge device limit, emergency descent. This checklist says not one thing about "DO NOT EXCEED." It's simply 275.
My thought is that maybe Boeing wants you to keep the engines moving and forget about the MMO. i.e. You're more concerned with high airflow than high true airspeed - you're not worried about an overspeed at this point.