Agreed.The thing is, it isn’t difficult to teach. Anyone who can describe technique and movement should be able to do it, if they understand it. It isn’t vague or mystical. I’ve done it many times here in the forums.
But it does take a methodology to build the skill, and a lot of work. I guess if there is no methodology in place, then it can be unclear how to proceed. Understanding the goal is one thing, knowing how to achieve it is another.
Oddly, I find some of these drills most helpful for folks who struggle with conventional drills, because deliberately trying to use their legs to power, for instance, confuses them. Giving them a drill that has a different focus (but in the end produces the same muscular movement) works better for them. I think it’s because of the way the restrictive part lets them not pay attention to something else.
The most notable example of this was a young woman with a neurological disorder. It wasn’t severe, but did affect her motor coordination. Traditional drills were much easier for her to work with, and got her to proper mechanics. I also find many of them work well for solo practice after they have some kind of grip on the actual mechanics, so I tend to use them either for helping folks who are struggling, or as add-on drills after they’ve started getting the concept.