You can also put on a windbreaker or sweatshirt. then remove the left arm from the sleeve. Use the sleeve in the same fashion as the rope to feel extensor action.
Thanks for all the help. Even though this thread has mutated into something different, all the advice is solid. The thing that worked well for me was allowing the club to drop from the top and let the pivot catch it-- great compression! I also tried swinging with a shaft on the legs and that helped to see the leg action better. However, you can still slide a bit and not hit the shaft, but it is not fun when you slide too much. Thanks again for the drills.