[comdpa]

You have described the Swinger's Standard Wrist Action (10-18-A) and its Sequenced Release (4-D-0)which requires the Left palm to be Swivelled On Plane during Start Up. It remains On Plane with the palm riding the wheel rim until the Release Swivel takes place, rotating the Shaft back on to its own Plane, ready to apply the selected Hinge Action (usually Dual Horizontal).

The Hitter has identical Left Hand to the Plane relationship as the Swinger at the Top, however it got there in a different manner. Instead of a abrubt Start Up Swivel, a Hitter turns his Left Wrist gradually just like an Angled Hinging motion. And so it comes back down into Release in the same way, a Simulataneous Release Motion.

For the hitter, the left wrist turns and rolls not on its own accord but because of the turning of the body and the motion of the arms.

Different Left Wrist Actions produces different Right Forearm Positions at the Top Per 7-3.

"For Hitting (10-19-A), the Right Forearm should be precisely in-line with-and directly opposed to-the motion of the On Plane Loading Action (7-22) of the entire Primary Lever Assembly (6-A) not just the Clubshaft, and this alignment maintained through Impact (2-J-3,4-D).

For Swinging (10-19-C) the Right Forearm should be precisely in-line with - and directly opposed to - the motion of the On Plane Loading Actino of the Secondary Lever Assembly (the Clubshaft) and this alignment maintained through Impact."

In English, this means that at the end of the stroke, the hitter will (should) have the Right Forearm perpendicular to the Left Forearm and the swinger will (should) have the Right Forearm perpendicular to the clubshaft.

This is a valuable checkpoint to see if you are actually executing the desired Left Wrist Action correctly.