Reading some other posts of yours after I originally posted this helped clarify that you are not really brushing above the fall line rather standing against an edged ski to turn. So I think you understand the ski likely is not brushing laterally above the fall line though I understand your intent to stand against the ski without imparting any rotational torque is the same. If you believe it is brushing, then my question is, what is causing that lateral brush? It's either a push or a pull. If it is a push, it is not coming from a released ski and if it is a pull I don't see how it is coming from any significant centrifugal force at wedge turn speeds and the fact you are releasing the downhill ski's grip, unless you are hauling the mail? Can you see my point? Just looking for clarification and understanding.
Because the skier is balanced on the sweet spot of the ski, essentially the functional center of the ski, and because the ski is tipped but not to a critical angle that creates edge lock, and because the ski is generating the turning force by nature of the self steering design of the ski, the tip and tail do not travel in the same exact, track. The track is wider than an edge locked or pure carved turn. YM