certainly not trying for a uniform theory, even tried to convey the kinetic chain theory can guide observers in maximizing their limb function in the first post. Learning movement though begins with the development of the trunk and spinal self manipulation, the control of our limbs and their freedom to be so dynamic is dependent on the pre movement of the trunk and spine and yet a majority of movement based activities continue to teach based on the reverse methodology. Obviously it works for many, but for many it is a lifetime of tinkering and never feeling comfortable or being able to reproduce efficient/pleasurable movement.
Good logic HS, but wouldn't that leave the head and eyes as the last part to respond to the forces of the turn? LF, I said energy, but a better word should be the force generated. The neccessity for having a free neck, head, eye function is something many talk about here for anticipatory needs, so something is working outside of the kinetic chain it would seem. The same could be said the instructions for hand and arm use, those are acting outside of a kinetic theory paradigm.
Call it adaptive, call it whatever words you like, but look at the mechanics of the man's movement, it is no different, he uses the loading and unloading of the forces in conjunction with a highly dynamic trunk control. Is he manipulating the ski and turn dynamics, if yes, then how, and could this control be even more critical than the limbs?