Liam,
Good bump. I, too, like Skinerd's openness and lack of ego in the Epic threads, it seems like he's simply interested in improving. Some very nice skiing on the glacier, I sure don't approach his competency.
I did smile at one Epic post stating that if you can't make a turn showing the same body positions that Helluvaskier can get into, then you should not be commenting on what is good ski technique. In digging through the Epic threads, I came across the below discussion of the CSIA "form follows function" concept of teaching skiing. It's a little long and not real concise, but, one does get a flavor.
My sense is that to understand CSIA's concepts, one has to do a lot more study to understand the definitions and intent of the overviews. Not surprising as simple systems are just too limited. A good ski turn is a very choreographed sequence, and, there is a lot to get right. The "ying / yang" at work: simple concepts that have much depth to fully develop. My 2 days on skis this year are living proof that there's a major gap between my goals and my competencies. Carving is much closer to skidding to-date.
Still, I prefer the PMTS concept of teaching movements. It's just clearer in my brain as to what I'm trying to accomplish on the hill. To each his or her (I hate being politically correct in writing) own, not preaching or ranting, but movements are simpler to understand.