[no_mind_golfer]

Pistol, I'm not sure I understand the question. Let me say this:

At every point in the golf swing the equations of motion apply ( F=ma and M = I alpha) These are of course three dimensional. Im mass in the parts of the system gets redistributed then that changes the moment of interia (I) in the second equation.

F (force) comes from gravity (small contribution minor really) and muscle contraction. When those force act on levers they cause Moments (M) which create rotation.

Muscles and gravity do not create central forces so as it is strictly defined in all physics/mechanics texts, COAM does not apply to the golf swing.

nmgolfer what about using certain forces to shift the center of mass forward to create an "instantaneous" axis of rotation for the pelvic region?