Hi, just checking in and thought I would respond to this question. As quoted above, Mr. Kelly is incorrect, as the head can be of prime importance in the wt. shift particularly in swings with limited wt. shift, although it certainly can be an initiator of large wt. transfers.
Further, it does not have to induce swaying! Perhaps Mr. Kelly had more to say about the subject than 7-14 or perhaps he corrected himself in his later notes?
Also, not only can the head be of prime importance in the rearward wt. shift, it can also be of prime importance in the forward wt. shift in certain models.
Additionally, it would be false to state knee motions invariabley induce swaying. In fact, correct knee actions can help in wt. shift and at the same time, prevent swaying!
This subject requires a further explanation than this, but I'd rather not get drawn into further debates at this time. I would prefer to demonstrate at a future time. Kind regards.