[Jeff]

Mike - I generally agree with your position that COAM could theoretically be acting on a rotating system while energy is still being inputted into the system - like that rotating structure in the U-tube demo. However, it would be very difficult to quantify the effect of COAM on the speed of rotation of the entire system while the person is actively spinning the rotating system. Secondly, the principle of COAM applies to the entire rotating unit (how its overall speed of rotation is affected by the distance its mass moves away from its central axis of rotation) and it has nothing to do with the transfer of energy from one moving body part to another body part. In the kinetic link theory expounded on the Xenolink website, there is an evidence-unsupported belief that energy is transferred from the pelvis => shoulders => arms via "a conservation of momentum" principle that involves a braking phenomenon whereby the slowing of rotation of one body part causes another body part to speed up. . Can you understand the physics/biomechanics that could underlie such a "belief". I can understand the kinetic link working in a snapping whip, whereby the sudden braking action of the rope handle of the whip transfers energy down the length of the whip to its peripheral end thereby causing the peripheral end to speed up. However, the whip is a totally inert physical structure that doesn't generate power within itself - it simply responds to the hand movement of the person wielding the whip. During a golf downswing, a golfer is actively contracting a multiplicity of muscles that cause the pelvis and shoulders to independently turn at a certain rotational speed. There is certainly an interaction between the rotating pelvis and the rotating upper torso - in the sense that the movement of the lower torso transmits physical forces to the upper torso via the spine and truncal musculature/ligaments. However, the golfer is also actively rotating the upper torso during the downswing and it would require some very sophisticated experimental testing (using muscle probes in a variety of truncal muscles) to determine how much of the upper torso's rotational speed is due to active torso muscle contracting versus passive physical forces transmitted from the rotating lower torso. I have never heard of any researcher performing that type of experimental testing. Have you?

Regarding your concept of the TGM pivot-stroke swing - do you think that the pelvis/shoulders/arms are rotating at roughly the same speed in the early downswing - before the lead arm reaches the parallel-to-the-ground position; or do you believe in the kinetic link theory where there is a time-sequential transfer of energy that causes the pelvis to move first, the shoulders second, and the arms third with each sequentially moving part maximally rotating at exactly twice the speed of the preceding moving part?

Jeff.