The 'impossible' turn is not quite so impossible, but it DOES require training and stringent decision making discipline, commit to one course of action and do it all the way to the ground and stopped.
During my Bonanza Initial at FlightSafety Beechcraft Wichita many many moons ago, we did several impossible turn exercises in the sim, and more often than not they came down to recognition of the failure, and immediate decision to act/configure the aircraft. Also did some exercises in the plane (at altitude) to demonstrate the feel.
This is one of those issues that has people strongly on one side or the other.
My position is if you don't want to ever attempt the turn back, don't. If you haven't trained/practiced it, dont.
Ideally, you should know what the minimum altitude/airspeed/configuration is from which you can RELIABLY make a safe return to the field, for each aircraft you fly.
But if you have trained/practiced it, and the situation calls for it, do it.
'Gimp