[Yoda]

As far as #4... what about 3 Barrel Hitting? No #4, or just very pasive?

Hitting or Swinging, any use of the Right Shoulder (the Pivot) during the Start Down to 'Load the Lag' (overcome the initial inertia of the Lagging Clubhead) constitutes the use of the #4 Accumulator. Otherwise, its Motion is only that -- Motion (a 'permitting' function) -- and not Action (actively causing something to happen).

So, when the Hitter uses his Right Shoulder to Load the Lag during the Start Down, he is using Power Accumulator #4. And assuming he is also using his Right Elbow (Bend and Drive), Left Wrist (Cock and Uncock) and Left Hand (Turn and Roll), he is using a Four Barrel Stroke.

It is doubtful the Hitter would use #4 in a Short Shot. More likely, he would use Drive Loading (10-19-A) to Load the Right Elbow and then use the Right Shoulder simply as a Launching Pad from which to Drive the Lag into Impact. Assuming the Left Wrist and Hand were also actively employed, then this would constitute the Three Barrel Hitting Stroke.