John, you are clearly no fool. But there is much that you still do not understand. Do not take that as an insult, or a slam--you are, by your own frequent admission, a novice skier, discussing a highly advanced move. I commend your effort, your curiosity, and your accomplishment. Your ability to analyze the details of movements without losing the perspective of the "big picture" will come in time. For now, I believe you are envisioning two accurate, but virtually incompatible (in the same turn) concepts. I'll do my best to explain why.
As I have described numerous times, only two things can happen when you transfer weight from one foot to the other. EITHER your body (center of mass) will move toward the new support foot as you push off from the old support foot, allowing you to keep your balance, OR you will start "falling" away from the new support foot because you did NOT push off. Both can happen at the same time--when the pushoff is not vigorous enough to move you completely over your new foot, it will at least DELAY your "fall" the other way. But there is not a third option. Clearly, the weight transfer does disrupt--accelerate--your center of mass one way or the other!
And remember--the wider the stance, the more dramatic will be both of these effects. The "fall" I have described is what you have correctly called an "acceleration of the center of mass." If you transfer your weight from the downhill ski to the uphill ski, and you do not push off to move your body up the hill, you will indeed cause your CM to "accelerate down the hill." And that disruption of the motion of the CM can be very useful at times, as I described in my previous post.
Your analysis of all these individual components is absolutely correct. But the key to the "whole" is how you blend the two possible effects of weight transfer, regulate them with stance width, and combine them with the other forces involved in the turn (namely, gravity and centrifugal force). We can analyze this to death, John, but actually exploiting these myriad combinations of movements in useful ways, or just for fun, is the very definition of expert skiing. It involves finesse, refined balance, split second timing, experience, and highly developed "perceptual skill." The practical application of these concepts is neither simple, nor, as I've often asserted, black and white.
To your point, then--
|the move actually accelerates the CM down the hill, not slows it down
Well, yes, it could, as I have just described again. And that is certainly a good thing if--and only if--you NEED to accelerate your CM down the hill. As my previous post describes, this is often NOT the case, especially if you have managed your previous turn perfectly. But for the sake of argument, let's say that, in a particular turn, for whatever reason, you DO need to accelerate your CM down the hill to get your direction change going. If you want to go DOWN the hill quickly, you would certainly do well to transfer your weight to the uphill ski to help accomplish your objective.
But I must ask you, why would you then want to transfer your weight to the uphill edge
of your uphill ski, causing it to continue to carve up the hill, as you have clearly described? When you do that, suddenly your skis and your CM are going quickly in opposite directions. Yes, this certainly hastens your "lean" into the new turn, but when your feet and your CM are accelerating in opposite directions, you are REDUCING pressure to your skis. When that happens, you will find yourself way over-committed to the inside of the new turn, with little centrifugal force, and both gravity and your own movements conspiring to make sure you don't have enough pressure on your uphill ski to start it carving down the hill. I hope you can understand this from my description here, John. I can assure you--it is easy to demonstrate on snow. If you really want to exaggerate the effects I'm describing, try it on a very steep hill. Wear your helmet!
So you can see that, while you are correct that a weight transfer CAN "accelerate your CM down the hill," that is not generally its role in the "inside-outside" weight transfer. That is why the "I-O move" is typically used to DELAY your "dive" down the hill, and carry your motion more across the hill, or even up the hill when combined with a lateral or diverging step, or when allowing the uphill ski to carve up the hill for any length of time. This is accomplished by truly shifting your BALANCE toward the uphill ski, at least somewhat, when making the weight transfer. To the extent that you do that (shift your balance--CM-- toward the uphill ski), this is a "negative movement" as I have defined it. And this is one of the reasons Harald usually advocates a narrow stance--precisely to MINIMIZE the "acceleration down the hill" caused by a weight transfer!
"NO!" you say. "That's not what I'm describing! It doesn't require the use of my helmet when I try it!" I'm sure it doesn't! But let's see why not.What combinations of movement and timing could result in an "inside-outside" weight transfer not causing the outcome I've described? Well, you could push off from the downhill ski as you transfer your weight, literally pushing your body toward the uphill ski, allowing you to balance on the new ski. This will work, but it is hardly the "acceleration down the hill" that you describe.' It is, in fact, a "negative movement" in the context of of a turn down the hill. BUT--it is a "positive movement" in the context of a turn UP the hill, or AWAY from the direction of the next turn. Again--that is one very good use of the "I-O" move, especially with the old skis. They allowed you to carry your speed ACROSS the hill, or even up the hill, delaying your "dive" into the next turn--very useful when the next gate is "way over there" and your downhill ski can't carve a tight enough arc. It was commonly combined with a diverging step in the direction AWAY from the next turn--i.e. up the hill. The common term "skating step" describes this movement well. If you wanted to skate immediately DOWN the hill, you'd do just the opposite movement--you'd push off from the DOWNHIILL edge of the uphill ski.
I hope I've pointed out that, among the many possible combinations of movement that could all fall under "inside-outside" move, the one that makes the most sense, and that makes the best use of both skis, is the skating step I've described, used when you want to carry speed across the hill and delay your new turn. If you REALLY need to get far back up the hill--let's say your hat flew off and you need to go back up and get it--you will REALLY push off up the hill, disrupting your CM intentionally from down the hill to up the hill. But that's usually not that much fun, and not what you try to do in every turn, I'm sure. The classic "skating step" that I believe you're looking for, in terms of this discussion, involves a complete transfer of pressure to the uphill ski at the end of the last turn, combined with a PARTIAL move of your CM toward that ski--not enough to really move it up the hill, but enough to SLOW its movement down the hill. This allows the momentary carve on the uphill ski you've described, even as your CM continues down the hill, rolling the uphill ski eventually off its uphill edge and onto its new inside edge. All this MUST be combined with the right speed, timing, ski type, and hill pitch to allow you to get enough pressure on that uphill ski to start carving as soon as its new (big toe) edge engages. This is the turn I have described many posts and pages ago. It is, indeed, a lot of fun when you get it right.
If you really want to experience a turn with a lot of "acceleration of the CM" into the new turn, try the "inside-INSIDE" move, as I have previously suggested. This move, too, involves a complete weight transfer to the new ski, with no pushoff or movement of your CM in that direction. It's usually combined with a step to the side to increase the CM acceleration effect (essentially, a wider stance), and a CONVERGING ("wedge," if you will) ski so that it can really engage and start carving immediately when you step on it. It has to--remember, you're moving AWAY from that ski, quickly, so you need it carve strongly and immediately back toward you to "catch" you. Furthermore, these turns typically must take place not far from the fall line--little movement across the hill--also out of necessity. If you try to pressure and carve the downhill edge of the uphill ski when traveling across the hill, especially when it is steep, there are no forces for you to resist, and therefore, your ski cannot carve! Yes, you can MOMENTARILY apply pressure where it does not otherwise exist, by quickly extending against your ski, but this pressure will not last (it's the same movement you'd make to jump up off the snow!) Sustained pressure must--MUST--come from your skis pushing against you, and not the other way around.
So you can see that an "early weight transfer" that accelerates your CM down the hill is incompatible with a move to the uphill edge of the uphill ski so that it carves away from the new turn. Both of these things can happen, but they rarely succeed together! (I won't say never--with enough speed, perfect timing, and not-too-steep a hill, a very tight carving ski WILL carve back underneath you and "catch" your CM that had been accelerating away from it when it was on its uphill edge. And I'll agree--trying to make this happen would be a worthy pursuit!)(continued next post....)