I think there is lots of nuance between theory and application. Some people are really good teachers, and good teachers can give us mental models are abstract enough to get the gist of things.

Roger Federer would say he never knew what kind of grip he used on his shots(which is one of the first things one learns as a beginner), and I think Roger might not be an elite coach, because so much of his greatness may have come from a very intuitive understanding of tennis. (Would I still take him as my coach, heck yeah).

I think some people have really intuitive understanding of their subjects and can express that understanding in amazing applications, but they lack the communication skills, patience, or language to properly pass on the knowledge to others.