Frame #3 -- The Middle Mechanics
Shoulder rotation and the "un-shrugging" of the lead-shoulder continues to force the hands around a circular path. The lead-arm is now almost straight. The back-elbow has lowered to the batter's side (in the "slot"). The back-forearm is rotating down toward horizontal. Note that the bat remains in the plane of the lead-arm from initiation to contact. The lead-leg is straightening to drive hip rotation as the speed of shoulder rotation starts to outrun the hips. Also note, the back-shoulder does not just drop, rather it rotates to a lower level as it follows the swing plane.
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