Fluttering control surfaces can transfer energy to the fixed surface very easilly... The rudder moves right, the rudder-fin are now airfoiled "lifting" left... then the rudder waves over to the left and they are lifting right. The sudden change in direction of force can be an immense shock load. (not to mention the dynamics of that rudder's mass swinging back and forth) You can litterally rip the fuselage in half this way.

Never underestimate the power of Flutter. It can break ANYTHING.

Who said it was a torque being passed across the hinge? BTW you CAN you can twist a hinge 90 deg to the direction it is meant to move... you will transfer a LOT of torque via the hinge.

Never said a plane DESIGNED to fly with no rudder wouldn't fly without it. Plenty of 2-channel aileron-elevator slope gliders do it all the time. But you rip the empanage off a conventional aircraft in flight (OFF, not held by the covering as with the Kadet pictured) and I defy you to keep it in the air.

BTW.. if that Kadet's fin wasn't held in line with the airflow by the covering on the right side... it wouldn't have had a snowball's chance in hell of getting down intact. (and I note the rudder pushrod is still attached...)