[Yoda]

Hinge Action is a Left Hand Motion through Impact that controls the Clubface by maintinaing the Flat Left Wrist Vertical to one of the Three Planes of Motion. As such, though it may have the appearance and Feel of a 'Roll,' it is not a true Rotation. Study 2-G and Sketch 2-K #5.

In contrast, the Swivel is Left Wrist Action that on the Backstroke, Snap Turns the Vertical Left Wrist On Plane, or on the Downstroke, Snap Rolls the Turned Left Wrist Vertical for Impact or the Vertical Left Wrist back On Plane for the Finish. As such, it is a trrue Rotation. Study 2-G and Sketch 2-K #4.

The Swinger's Total Motion has three Swivels: The Start Up Swivel; the Release Swivel (that mirrors the Start Up Swivel); and the Finish Swivel (out of the Follow Through Interval). The Hitter's Total Motion has only the Finish Swivel.