Correct me if I'm wrong but I always thought that TGM advocated a Hand Controlled Pivot. Starting the downswing with the Pivot per 6-K-0 tends to throw the shoulders at the ball, and that 6-L-0 was far better as the shoulders are undisturbed by this initial move from the End. Drag Loading can still be accomplished with solely the hands and arms, and once complete, the Pivot "kicks in" to maintain balance through the remainder of the swing. That's the way I've been swinging -- and with good results may I add.
Hands controlled pivot does not mean hands powered pivot. In the swingers procedure, you create a pressure at pp4 against the primary lever assembly to drive it through impact - pp3 aims at the aiming point - to be able to do this you must have the right shoulder go downplane.
PP4 - pivot pressure driving against the primary lever assembly
PP3 - passively directs the lag pressure