I would strongly concur that it's the teaching. I may not know a whole lot about jiu jitsu but I do know quite a bit about teaching and learning. Teaching well is its own discipline and subject matter expertise alone is not sufficient. A teacher has to have a robust knowledge of not only their subject but a good working knowledge of how people learn and how best to communicate an idea or ideas to a mixed group of students. That's not an easy task.
A good teacher/coach has a plan of instruction and prepares a curriculum with intent. It is not a haphazard "Hmm... what should we go over today..." approach. Subject matter expertise is, of course, necessary for the instructor to be able to go beyond the lesson plan when questions arise and to explain the theoretical underpinnings when necessary (e.g. why you do the set up for *this* technique *this* way because doing it *that* way opens you up to such-and-such a counter, etc.). A good teacher has more than one approach to a lesson and he or she is aware that individual learning needs differ and will adjust as necessary.
Jiu jitsu is especially well-suited to a social learning theory approach. Social learning theory utilizes the idea that the environment is a key component of the learning environment in addition to integrating subject knowledge, task knowledge, and task performance. I know Coach Herzog uses primarilly a social learning approach. He has a series planned well in advance and the techniques progress logically through the whole series across the technique classes; meaning if you go to noon beginner class on Tuesday and 7:00pm beginner class on Thursday you're going to see the same series. Not a kimura attack Tuesday and a leg lock on Thursday. Typically, the series will also incorporate both the attack and defense aspects so both partners are getting reps instead of practicing attacking a fish.; In this way, the student learns to attack against a properly defending opponent using proper technique rather than relying on a opponent's lack of knowledge or gambling that he has weaker technique or position knowledge (which is a criticism I have heard of the 50/50 guard). Technique class is for practicing controlled movement and perfecting the muscle memory under close supervision and with frequent corrections and tweaks from coach. At the end of technique class are one-minute drills. During these, coach starts the class in a position that is advantageous to one player. The goal is to resist about 60% or so and to rep the technique(s) we've been working . Some guys get off track and treat it as "one-minute rolling" but that's not the intent. The point is to drill the techniques you just learned against a resisting opponent who knows what you're trying to do. Yeah, that makes it hard but that's why you drill the technique. Then there are always open mat and rolling sessions. So from a social learning standpoint you have planned curriculum in a logical progression, slow technique practice, practice against resistance, and open rolling. The combination and progression is excellent for developing muscle memory, sensitivity, and application against progressively more difficult challenges. Most importantly, all of this is done in an environment conducive to training for competition -- and environment matters when it comes to developing and applying complicated task knowledge in a high-stress environment. Train the way you fight, practice the way you play, etc, etc.
There certainly are other approaches to teaching but because jiu jitsu requires both the mental strategy aspect and the physical application of technique, it is most well suited to a social learning approach. I'd love to hear how some other instructors approach teaching and learning; especially Mr. Green since I know a lot of military training comes from a social learning theory angle.
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