Originally Posted by HeluvaSkier
A few points for discussion:
- The Phantom Move (or whatever you want to call it), by its very nature uses inside ski redirection [rotary] at the very top of the turn in order to make the ski paths divergent. In a non-exaggerated turn this is so minimal that you can almost discard its existence (which has been done in PMTS) but the fact remains that the movement exists.
- The Phantom Move also puts the inside ski on a track that closely resembles the outside ski so that no further redirection has to occur after the point at which the move is executed.
- In a PSIA style turn where the inside ski is tracking a different radius from the outside ski (much smaller), the inside ski must constantly be redirected by using rotary or awkwardly tipped onto a higher edge angle than the outside ski.
While the tracks that have equal separation on the snow may look more pleasing to the eye making a turn that requires the inside ski to be redirected through the entire turn is not exactly what I would describe as an efficient movement (hence my reference to efficiency).
Now, someone brought skifex and her turns into the discussion. I would argue that he turns and her type of skiing do not completely fit the models that we are looking at... especially when you take the CM movement into consideration. [The only way that she can maintain weight on the outside ski with her skiing is due to centrifugal and centripetal forces between her skis and the snow and the snow to her skis as her CM is falling way inside of the turn. However... if you take ONLY her lower body into consideration you will notice a sequence that resembles the 'real world' tracks that I drew in the original drawing. If you look closely you can even see a move that lends itself to pulling back the inside ski...]
Seem t ome we are making alot of assumptions here.
#1, I don't know that the skis diverge from rotary, from the leg getting shorter, or from both happening at the same time, or other issues. Dynamicly pull the inside heel towards the butt, and you will get diverging skis, but you can also get there by simply unweighting the inside ski, countering too much and steering the ski along it's way.
I've never been in a pmts clinic, so I don't know how this would work out other than to say I have read book two, and played with the concepts.
#2, "Closely resembles" will still require some redirection or "guidance" in my view. The only way to get to no further redirection needed would be to have them in the same exact track and radius. As they say, close only works in horseshoes.
#3 What is phantom to me is that proverbial "PSIA turn". What is it? Aren't the skis always tracking a different radius? I mean, we talk of parallel tracking of the skis, but doesn't this require some guidance and redirecting whether it is a " pmts turn, or a psia turn"? Does parallel really even exist if the skis aren't are not tracking the same radius? I see the same thing happening with regards to the continual guidance of the skis in both of your types of turns that you want to draw a distiction too. The bias may differ between priorities, tipping versus guiding to keep a consistent width, but both require some guiding because neither have the same radius happening between the inside ski and the outside ski.
Skifex's skiing inefficient? Perhaps, but we would really have to scientifically evaluate the tension and btu's happening in the body to really determine this. Is angulation always more efficient than banking in terms of muscle energy expended? To me she looks realxed, fluid, and playfull. I've watched Nick Herrin skiing vey similar to this when he was being "playfull". Well those are my thoughts. later, RicB.