I also think some of this is in how teaching is done. I've seen instructors correct position of a limb, without ever getting into how the limb got there (principles of movement, and the answer to how it should be corrected) or why it should be in that position. Without those ever being discussed, a lot of students will misunderstand principles. I've seen people struggle with the same technique over and over, getting the same rote correction. Then another instructor gives them a little bit of the principle explicitly, and they are quickly able to make the correction.
Of course, it's possible to err in the opposite direction. I sometimes explain too much, which can confuse some (not all) students.
For a beginner, learning to control position of their limb is a priority. To be able to do just this is sufficient reason to simply correct - principle behind it not needed. You are right in that
how the limb gets there is important. In fact, the path the limb takes is just as important, if not more, as the end position. This is what gives the move function.
As for the instructor repeating the same ineffective rote correction to the struggling student - the instructor is simply unskilled. In this situation, it seems he is unable to recognize the problem's cause and/or teach that
critical bridge that allows the technique to be done correctly (in accordance with principles). But knowing the principle without that bridge allowing it to be utilized is useless. They need to know how to move and what that feels like more than the underlying principle. Their body will understand the principle, even if the mind does not at this stage.
I hope I am expressing well enough to make this perhaps abstract, but IMO, important and valid point. Consider an eight year old gymnastics student doing a technique. Do they mentally understand the biophysical principles involved? They learn by doing, their coach refining their dismount technique, not with explanation of the various forces at work, but with suggestions like, "Cross your arms sooner" or, "Raise your right hand like you're scratching your head as you twist." The coach recognizing these more subtle points being the key, fulcrum or "pressure point" of the technique will allow the student to better execute. Of course, the coach's corrections are based on physical principles, but the eight year old doesn't know that, doesn't care and doesn't need to know them. They just enjoy the feeling of spinning correctly and sticking the landing. They feel how to do it correctly.
To more fully quote Parker, "To hear is to misunderstand, to feel is to know."