Separation in skiing created 4 different ways.

The ski world calls it separation. I think that undersells it. What's actually happening is your body storing rotational energy, like winding a spring. The upper and lower halves move at different rates and that tension between them isn't just a shape you're making. It's energy waiting to be used. In short turns that energy is doing real work. Your body winds up through one turn and releases into the next, snapping the skis across the fall line faster than muscle effort alone could manage. In long carved turns the job shifts. The ski's geometry takes over and your role is to be strong, stacked and aligned. The separation here is less about rotation and more about angulation, staying powerful over the outside ski while letting the ski bend and grip. But even in a long turn that upper and lower freedom matters. It lets your upper body enter the new turn before your skis do. Stay too square and you become one rigid unit. The skis have nowhere to go that your whole body isn't already committed to. Short turns, wind up. Carving, stack up. Wind up isn't something you always want more of. It's something you tune to the turn. Nobody has built a robot that can ski beyond a complete beginner. I wonder how they'll teach it to feel when to store that tension and when to release it. In a good skier that instinct isn't conscious. It just happens. These animations are my attempt to make it visible. Save for later if this is useful.