|you will NOT see/hear this tech being espoused by the either PSIA or the other 'system', because they are simply unaware of it.|
This technique that you describe (almost--see below) has not only been well-documented by many PSIA instructors and examiners (including me) for a long time, but anyone who actually watches World Cup technique has certainly observed it. It's no secret to anyone with eyes! Nor is it unknown to any actively experimental advanced skier, which describes--by my definition--all top instructors. (Do not confuse that statement with "all instructors"!)
Here are a couple photosequences that I first posted here on EpicSki nearly five years ago, with much discussion. They were shot at the World Cup slalom at Copper Mountain in November 2001. Unless I'm reading you wrong, these skiers--especially Laure Pequegnot, who won--show quite vividly the exact fore-aft movements that you are trying to describe.
Gerg (second sequence) is not quite as active with the movement of allowing her feet to move forward beneath her hips through the transition. Nor was she quite as fast. Hmmmm!
And in this next sequence, Kristina Kosnick really misses the move in her last two turns--not intentionally, I submit, but due to a little too much forward (boot tongue) pressure near the end of the turn, which both pushes her body back and causes her tails to wash slightly, slowing her skis down:
(Note--to synchronize these animations, wait until all three load completely, then hit the "back" button on your browser, which will take you back to whatever page you were looking at before this one. Then hit the "forward" button to return to this page. The animations should now all start at once, which makes comparing the three skiers' turns much easier. You can quickly see how much speed Kosnick lost to Pequegnot with her "little" mistakes! Edit--sorry, the Gerg animation runs slower, so it won't synchronize, but the other two will.)
Anyway, there is one problem with your description, and it is one that often causes great confusion:
|draw your feet behind you, as far under the chair as you can, flat.
this is where your feet shoulod be at turn initiation.
now, slide your feetesses forward, until they are right under your knees.
this is where, in a great slalom turn, your feet should be in the crux.
now (you guessed it) slide them fwd., until they are well ahead of your knees, a sfar as they'll go, flat.
do whatever you like with your upper body, as long as it's all facing forward, and not rotating. (this is slalom we're talking, here).
see where your feet are? that's wher ethey should be at the finish of a fine, rounded slalom turn.
Now I realize that not all racing turns are linked--some have traverses between them--but the turns I've illustrated here, at least, are. And the turns most recreational skiers strive for most of the time are linked as well. Linked turns are where that sense of rhythm and continuous, cyclical flow that so many skiers lust after comes from.
So to make linked turns, by definition, whatever "position" you start one turn in has to be the same as the position you finished the last turn in. (I put quotes around "position" because I do not mean to imply anything static--these "positions" are but moments in continuous motion, like a doorway you pass through without stopping.) If you finish a turn in one position, and start the next turn in another position, those turns clearly are not linked. To link turns, you absolutely must finish one turn ready to start the next.
This is hardly a new concept. Phil and Steve Mahre, among others, were quite adamant about similar thoughts at least twenty years ago, when I started working with them at the Mahre Training Center at Keystone. Whether you're talking about fore-aft movements, edging/tipping movements, up-down movements, hand movements, rotary movements, or any other movements of linked turns, you have to make sure that you finish each turn in the same position/attitude that the next turn starts. Otherwise there's a break in the cycle. Otherwise you'll have to finish one turn, then delay the beginning of the next turn while you get to the starting position. The Mahres harped on this mistake as one of the most common and significant causes of racers being "late" starting turns.
Anyway, Vlad, you do appear to have an accurate eye when it comes to race technique, and I do agree with what I think you were trying to describe (forgive me if I've completely missed your point). With the one caveat that I've mentioned, I think you've described one of the most essential movement patterns in skiing today. And you are right that it's also one of the least understood. It certainly contradicts the conventional wisdom that you must maintain forward pressure on your boot tongues and that your hips must remain forward of your feet at all times. You are right that many instructors, as well as many race coaches even at high levels, continue to subscribe to these unfortunate notions.
But not all do. I sense some sort of a chip on your shoulder against PSIA and other teaching systems, which you are, of course, entitled to have. You should know, though, that there is no "officially sanctioned PSIA technique." Such a notion is anathema to PSIA's core philosophy of developing the skills of skiing, rather than dogmatically holding to any particular technique. With the Skills Concept(TM), originating in the early 1970's, PSIA transcended all traditional teaching methodologies (including its own "American Ski Technique") by exploring skills and the entire spectrum of movement options in skiing, allowing the instructor to focus on each individual student's needs ("humanistic approach," vs. "mechanistic") and developing whatever movements and techniques best fit the student at any moment, for any particular intent or purpose. It is an enlightened approach!
The Skills Concept(TM) also enables and encourages PSIA instructors to explore, experiment, create, and innovate--a far cry from adhering dogmatically to some "official technique." Of course, many instructors have little experience or training (certainly not all are certified or current). Some have some pretty "off the wall" ideas, and others have gotten stuck in a rut from the past. But PSIA is a loose affiliation of thousands of individuals, not a religion. Criticize the ideas of individuals, if you feel the need, but not the mythical edicts of the organization!
In any case, while these movements certainly are not "the" technique that PSIA espouses, they definitely represent a recognized and approved technique. "PSIA" is not, as you suggest, "unaware of it." You've got to believe that anything you see at the World Cup level is, by definition, an "approved technique"! And I agree with you that it is one of the keys to smooth, arc-to-arc carved turns. Where is it written? You just read it, didn't you?