How do you know he "produces exactly that result"? Being "stacked" is felt, not shown.**...
** I suppose there are cases where you can compare before &after of someone whose body is way out of whack when skiing in the Before, and is slightly better After, and say the stacking was shown. But focusing on what it looks like hides the real thing of how it feels. I can imagine someone watching Darren's vid and emulating the body posture and thinking "stacking" is happening even if it's not.
One problem with stacking as a concept is that it doesn't have a very precise definition. The closest you get in practice in my view is when talking to intermediates on down about getting out of the backseat. There, stacking is I think a helpful phrase, used in the context of stacking things vertically.
In terms of higher-level skiing, you can look at people who are more or less square to their skis who are equally good and equally "stacked" in terms of forces. To be as politically correct as possible, Lemaster has some montages of people like Cuche versus Defago showing this. What stacking at that level emphatically does not mean is keeping your hips vertically over your skis, or staying square ALL the time. Not saying the video in question was advocating this, but I think many people do believe -- and do get taught -- that stacking is a static posture.
Of course, you could say the same about counter and angulation, etc. in that they should not be static. For me, I just feel I know more what someone means when they use those phrases, whereas with stacked I need much more context to get some sense of what they are getting at. The video has all the subtle points in it in terms of not overdoing, not being static, etc., but for me I would have heard those subtle qualifiers better if he had started with a lead-in or preface saying, "This lesson is for skiers with X or Y problems..." Maybe even given a visual example of someone who could benefit from being a bit more square at points in a turn. That may be asking an awful lot and maybe I should be willing to work more when looking at youtube clips.
Edited by CTKook - 12/28/12 at 9:45am