Just kinda thought of this, so bear with me if it's not 100%
When a skier moves into the back-seat pressure moves no as much on the heel as rather onto the back spoiler of the boots. This creates a lever that lifts (unweights) the middle-forward part of the ski, effectively reducing the length of the ski.
So a 165 SL ski with 115-65-100 will have a radius of 11.5m (via FIS ski radius calculator) lets say that by being aft. you lose pressure in the first 15 cm of the ski, the new radius will be 1 meter WIDER!
this happens because the "new" tip is much narrower than before (95mm) while all other measurements remain constant.
So, what do you guys make of this?
Keep in mind that is not what happens when you actually ski on the tails i.e. the front part of the ski is off the snow. It should represent only the unweightening of the tips.
Sounds good in theory, but I think you will find that if you put even more pressure on the ski's tails in the way you describe, you will no longer have much bend in the ski in front of the boots. And therefore, no carve due to tip's shape being pressured into the snow. Rather the tips in front of the boots won't be on the snow much if at all (and the tips will therefore be free to pivot) and you will bend just the ski's tails into an even tighter arc than you can bend the whole skis. The flare at the tail (from the ski's shape) will direct the tails of the skis away from the way you tilted them which will direct the skis tails to track out further and pivot the skis at some point near the boots, and thus swing the tips downhill initiating the next turn towards the fall line. Then with a higher edge angle and because the tight bend in the ski's bent tails, the skis will carve a tight arc around the radius of their tail's considerable bend. The radius of the tail bend can be a lot tighter arc than the entire ski's bend because all your pressure and leverage are concentrated there on the tails. The resulting carved turn can be much tighter than predicted by the radius of the ski's shape.
I've tried to describe this before on EpicSki but have just been told I don't know what I'm talking about and that it won't work. Well, I may not know what I'm talking about, but whatever is happening, I can tell you from experience that it works and results in a tighter carved turn than I can make in any other way. A quicker turn than I've seen anyone else besides perhaps a slalom racer in a flush do. I suspect the slalom racers are using the same technique I am then. Ted Ligety certain knows how to do it that way as demonstrated by the carved 360 circle he made at the end of the Moscow slalom against Bode video that Tog so generously found and provided. I think there is further evidence that Ted is sometimes using this technique on the course because he gets too far back in the first race and loses a half second to Bode recovering from it after making a tight right turn around one gate. If I recall correctly, somewhere about 35 to 40 seconds into that Moscow race video.