Obviously, the speed at which a student learns is directly related to the abilities and amount of effort invested by them, but even then I often feel that schools needlessly drag out the training time.
Having said that, a student can only progress in skill over time, and experience always counts for something.
This is true and points to something else that's important about LC's ideas. He has, in other stuff that he's written (
Fighter's Fact Book, e.g.) pointed out that it's important to understand the katas in karate in terms of the effective techniques they record. Katas are
all about self defense, once their bunkai are correctly understood, and Christensen is part of that group of karatekas and, increasingly, Taekwandoists who do a lot of research extracting the simple, effective fighting moves from the patters those MAs teach. The complexity of the moves isn't in the patterns, it's in the technical (over?)elaboration that has come into these arts as a result of their increasingly exclusive sports orientation.
TKD is a good example of this because it's best known for its elaborate kicks. But if you look at the hyungs, not just for colored belt but for black belt too, within say KKW-style TKD, what you see are actually very simple kicks---and not many of them, either! Koryo, for example, has 30 moves, of which fewer than a third are kicks, and those kicks are the simplest and most street-effective ones---low and middle side kicks and mid front kicks. Ji Tae, a more advanced form, has 28 moves, only five of which are kicks---again, just basic front and side kicks. No 360 crescents, no gyros, just basic stable stuff you can use as effective finishing strikes. The emphasis in all the TKD hyungs is on hand techniques---elbow strikes, strikes to the groin and throat strikes (disguised as down and rising blocks respectively) and throws (camoflaged as basic punch-block sequences and weight changes in stances) and so on---stuff that if you train it right, will work in a real fight.
But Adept's point is critical here---to make those movements automatic, to really grind them into your neural programming so they become reflexive, takes a long time. It may not take a long time to present an effective skill set, but it's going take a long time before the practitioner will really `own' that skill set as a wired-in pattern of reactions to physical threats---a pattern that kicks in automatically as soon as it's clear there's imminent major danger.
The TMAs have got a ton of good stuff in them, and LWC is well aware of that, as his other writings show. But---as a zillion people on all kinds of different forums here have said before---it all comes down to whether, and how, you train that good stuff, and LC's main point is that many people need to make their training style much more realistic, if they want it to be effective for self-defense.