A properly designed and constructed plane shouldn't have such problems, the servos have more than enough power to move the control surfaces. If the servos can't move them, there must be some damage, so I don't see as it makes any difference worrying about what you do with the servos, the plane is probably crashing anyway.
What is more important is a fail safe on the radio system, so if the RC batteries go flat, or the radio link fails, it brings the plane down to the ground in a reasonably 'controlled' fashion - commonly by fordcing the rudder hard one way, and spiralling the plane down.