Joe,I am not sure about all of this Dave. If the player anticipates using the forearm muscles such as the Supinator, Flexor and Abductor muscles these muscles will tighten and loosen (as needed) before contact in anticipation and thus possibly provide more cue stick guidance. The psycho-neurological literature on anticipated muscle contraction / relaxation is quite clear. The extensor Policis Brevis and related wrist muscles have to be used in a different way than the pendulum swinger uses them and there must be anticipation here as well.
I am suggesting that any person who uses a piston stroke before or after contact is using these muscles before contact. The body simply readies itself for anticipated use and thus it could be expected that there would be some effect for those who intend to use the piston swing after contact.
I am not trying to nitpick here. I am suggesting that those who use a piston swing are using additional muscles to propel the cue stick before and after contact. To be more specific they are making added use of these muscles that the pendulum swinger is not intentionally using. The additional muscles may lead to a better quality of hit in the guidance they provide.
I'm no sure I follow your logic here, but thank you for the information. I see elbow-drop during follow through more as a relaxation process rather than a muscle-activation process. The cue and forearm have momentum after CB contact and they naturally want to continue forward, pulling the upper arm forward and the elbow down as a result. With a pure pendulum stroke, muscles (and the chest, if there is contact) must work more to redirect and slow the momentum.
With a pure pendulum stroke, I also see the upper arm as just part of the stance. Muscles have to work to keep the head and body still during the stroke (especially with more speed). To me the upper arm is just an extension of the body that a pendulum stroker also tries to keep fixed, just like the head and the rest of the body (except the forearm).
Regards,
Dave