There's good and bad in that, truth and fiction. Some of it is accurate, but much of it is defensive.
So, the truth- I'm shitty at teaching breakfalls. I've been doing them so long that I really don't remember how the early classes were set up. I'm good (clearly a bragging story: once in Dynamited Cave I fell off a simple climb. It was at most twelve feet total and easy so we weren't roped in. When I fell I was only maybe five feet above the floor... but it was the usual lava tube floor of broken up rock and aa lava. Sharp and hard. I landed in a perfect right side break fall, except that my body was bent and wrapped around all the significant sharp boulders. Some scratches, nothing else...but I was able to adapt a ukemi on a hard, irregular, sharp surface with the glance from a flashlight as it fell.)
Bragging, but the point is that I can tell you how to do it, maybe even make up some drills... but the only way to learn to do it that fast is to do it a lot in ugly conditions... but I don't clearly remember how I learned the very basics of ukemi. Sort of, but in my memory it seems like just a few minutes of training.
My son is getting heavily into gaming. He takes his world-building very seriously. He is trying to figure out the imaginary physical laws of an imaginary place. What the politics are, what the gods do... so little of that matters.
Do we live in an aristotelian, newtonian or einsteinian universe? Do you realize how little that knowledge, or the perspective, affects people's lives? Newtonian mechanics got us to the moon, but the average guy watching his TV and driving his car didn't know or care from Newton. If string theory proves to be true or if it doesn't will directly affect the lives of a handful of physicists. The rest of our species has lived for hundreds of thousands of years without even asking the questions.
My son thinks that worldbuilding involves having all the answers. He doesn't understand that it is supposed to be fun, and that means giving the players the right kind of questions. Human-sized questions. Questions they can relate to. Things that they can do in small ways, safely-- like talk to girls or stand up to someone scary... things they can barely do in real life.
Which brings up another puzzler-- people who are afraid to tell their boss 'no' fantasize about fighting dragons. People who don't understand their own wives and children and live in constant conflict feel perfectly qualified to criticize high-level diplomacy. People who do not know their own mind or the mind of their closest friends will tell you what God believes...
It may seem I'm wandering, but these things are related. I'm not talking about action under stress right now. I'm talking about training. When we (I think most will agree, hence the we) denigrate training or training methods, most of the time it has nothing to do with us forgetting our baby steps. None of us popped out of Zeus' head ready to rumble. We remember, sometimes painfully, the slow progression and the learning curve.
What we do see is the hours and the effort spent on things that are completely irrelevant. The training for attacks that don't happen. The inbred layers of defense and counter that only apply--or work-- in house. The minute dissection and bickering over details... like criticizing the penmanship in the Declaration of Independence.
Too many hours spent building things-- whether physics for an imaginary world or series of actions to respond to a wholly imaginary attack that don't exist and wouldn't matter if they did. It's a human sized world with human-sized problems. Learn to deal with those and you'll see some deeper connections.