Just my belief here, but this can be taught easily, just not so useful for stalls. If you start from lesson 1/2/3 or whatever lesson you teach rudder use for turns the student will be telling you when you screw up a turn by lesson 10. For uncoordinated rudder on turns the "feeling it in your butt" is a great technique for learning the right pressures, for stalls, not likely.


Edit: Ooops to address the rest of your comment, stomp on the rudders and feel that motion. Then enter a turn (the CFI should demo this) without rudder at all and using a good roll rate and the student will feel their butt shift from side to side. Now do a turn entry again with the proper amount of rudder and vuala, no butt movement. Soooo, no butt movement = coordinated.