Yes!I agree with so much that has been said, particularly @James nailed it IMHO. I want to stress the fact that movement based teaching and analysis is not an alternative to the outcome based approach. They are complementary. I am learning, not teaching, skiing. But I learn faster when my instructors use a combination of both.
The other thing to stress is that ambiguities are problematic. As @john petersen and @Monique were alluding, instructors in a same institution (say, PSIA, USST, CSIA, etc) will have catchy terms for complex concepts. While those serve them well when they work together, they mean little, on their own, to people outside their circle.
I would say, most of us (all?) think Mikaela Shiffrin's skiing is exemplary. How we call her upper body's behavior is subjective. But we want to do something that resembles that.
So, going on a long conversation, back and forth, whether your upper body should be quiet, or steady, or controlled, or counter ... is futile.
Well, it does serve pugski google analytics to a point, but we'd much rather see a new healthy discussion instead of a debate that seems to circle, as if its doing down the drain.