My humble thoughts in the matter...
From what I understand of knowledge such as this (where you have to do it/ practical rather then theoretical), learning comes from experience.
The teacher is necessary in order to provide the proper experiences and guide you in understanding those experiences. But learning it, comes from the student.
Anyone who goes to class and expects the teacher to teach him good ukemi or technique or whatever, and never even bothers to practice beyond the classroom time is going to have a rude awakening.
That I think is the best part of this type of knowledge.