Yes, good points, FatOldMan!
At lower speeds, such as linked "basic parallel turns," where your feet remain constantly in contact with the snow and the least amount of pressure the skis will "feel" will be your body weight (at most), the "inflection point"--the actual moment of the direction change, the moment the mathematical direction of curvature of your path changes from right to left or vice-versa--will occur at the moment of edge release. That's the moment the skis let go of the mountain and stop resisting the pull of (a component of) gravity down the hill.
At higher speeds, or whenever the transition entails complete "weightlessness" for any reason, the "float phase" will actually involve a brief period during which the skis and the body (cm) travel in straight lines on crossing paths. (At least when viewed from above--since gravity still pulls toward the earth's center there will still be acceleration directly downward, but there is no component of gravity acting parallel to the plane of the hill--in other words, when airborne, gravity does not pull us down the hill.)
Thus, to your point, "release" can take on a whole new meaning that entails much more than simply "edge release." At the end of the "shaping" or "pressure" phase of a dynamic (high speed, high-g-force) turn, if we've done our job well, we can release everything--release all effort, decoupling the link between between our skis and our center of mass, and allowing the momentum of our bodies and our skis to continue unimpeded through the transition. Since they travel in different directions and at different speeds, the paths of our feet and bodies cross, causing the new turn to begin with--literally--no effort whatsoever, and no movements that begin at the initiation.
This transition--which should be quite apparent in the clips in my previous post, represents to me the epitome of efficient, flowing, great skiing. It produces the sensations of effortlessness, floating, flying...intoxicating sensations akin to the sheer exhilaration and joy of swinging high on a swingset when we were kids. And, since the transition involves literally no forces or effort, only the continuation of already-existing motion (according to Newton's First Law--"a body in motion continues in a straight line...."), it also demonstrates quite clearly what I mean when I say that the "things we must do" to start a turn must take place well before the turn actually begins.
It's one of the notable distinctions between the skiing of experts and of almost everyone else. Most skiers make their biggest movements and efforts in the transition, then "brace" with very little motion through the rest of the turn. By contrast, great skiers tend to exert the LEAST effort in the transition, while moving continuously and with clear purpose throughout the turn. Of course, as I've so often noted, most skiers aren't even trying to do the same thing experts are trying to do. Experts, at least in these turns we're discussing, are trying to minimize the energy loss from turn to turn as they maximize their glide and manage their speed through tactics and line. Most skiers are actually trying to shed energy and brake when they turn, controlling speed directly with braking technique rather than tactics. This vastly different intent alone--even more than the difference in skill level--explains much of the contrast in technique.
Bob - this makes so much sense after skiing with you during the Synergy Camp. Thanks for an eye-opening two days of skiing. I was up again this week-end and can already feel a big difference in my skiing (both piste and in bumps). Regards. GettingThere (Rahul)