Airfoil,
You're normally on top of the aerodynamics questions, but I'm gonna have to disagree with you on this one. Take the term "coffin corner" out of the picture and think about maintaining an airspeed while reducing power. You do this every time you begin a descent for landing. Pull the power back, nose over slightly and you can maintain any speed you want right out to Vne. Or 1.05 Vstall for that matter. Just control airspeed with pitch and vertical speed with power. Standard "backside" stuff that you learned way back in your PPL days.
I'm a bit intrigued, actually, at how often the coffin corner comes up in this forum. It's fun to think about when you're talking U2s and such, but it happens at altitudes so far above what's reasonable for flight efficiency, I can't imagine an airline driver getting anywhere near it in normal ops.