I don't think there is any need to talk about femur rotation in pure carving! It happens naturally as you increase/decrese edge angle. It makes far more sense to talk about tipping and angulation, but the problem is that people are so deeply ingrained to the idea of rotation, that they need to talk about it even for pure carving.
There is a difference between what I tell a student and what I say to instructors when I am training them to observe and analyze effective and ineffective skiing. Instructors need to understand the importance of rotation, so I need to talk about it.
I don't think anyone has an "ingrained idea of rotation..." More often, people have a habit of rotation that they are completely unaware of. It develops in most skiers, regardless of how they were originally taught, because that twist at turn initiation creates immediate pressure, and a sense of control.
I've found that sometimes effective rotation happens naturally, but more often poor upper/lower body separation and lack of rotation (which are related, if not identical) prevents skiers from balancing accurately. Like any other skiing skill, some people get it immediately, others need lots of coaching.