Hi Heluva. I wanted to practice my MA skills, so Max_501 suggested I stop by your thread. I can see the heavy lifting has already been done, so here's the only observation I can think to add (besides that this is great skiing): Regarding your arm position: In slow motion, I played back the first sequence of you in green and black, starting at 0:16. First I focused on just the right hand, then I repeated this focusing on the left. When I did this, I noticed the right hand/arm generally stayed forward/strong; it was principally the left arm/shoulder that had a tendency to rotate back. And I saw this both when it was on the inside and on the outside. I'm not sure if the asymmetry is inherent to your skiing (maybe a difference in hip rotation mobility between the two sides?), or if there's a double fall line there that might be contributing to it.
Also, if you wouldn't mind three bits of speculation (Harald did say we should stick our necks out...):
1) It may be that the hunching during the transition is due to boot ramp angle. However, I'm wondering if it might instead be due to the mental instructions you're giving yourself. I notice you make great effort to keep your CM from rising during the transition. However, if you're monitoring that using the height of your head or upper body as a cue, that could be causing your hunching: At the transition your hips naturally come up a bit, which could cause you to fold at the waist if you're trying to keep the head/upper body at a constant distance from the snow. [Another mental cue that can cause folding at the waist is "stay forward," if it's focused on the upper body, but I think it's less likely you'd be doing that.] Can you recall if you're using a mental cue for your upper body that could be causing the hunching?
2) Regardless of the cause of the hunching, I'm wondering whether starting the transition with somewhat of a hunch might be interfering with subsequent development of CA/CB in the turn, and thus whether your CA/CB would improve if you reduced the folding at the waist -- as you know, our alignment and movement in the transition sets up the rest of the turn. I experimented with this on dryland by supporting myself with my arms between two countertops, and trying to move into counter from a transition starting both with an without a hunch. The former seemed harder. You can experiment with this yourself and see if the internal sensations you feel correspond to what you remember from your skiing.
3) As has already been pointed out, your skiing here is so good that we can only nitpick. If you want to take your skiing to the next level, you may wish to consider making that same variety of turns on steeper and/or icier terrain, and posting the video. If you're human like the rest of us
, that should allow any errors you are making to reveal themselves much more clearly. It's like giving an exam to a grad student on which she gets a near-perfect score: the exam wasn't hard enough to reveal the limits of her understanding, which is the first step to increasing it.
Again, beautiful skiing!