Teaching literacy and arithmetic are pretty fast. So is a lot of Feldenkrais and Alexander Technique, first aid, or basic swimming. I don't see any strong generalizations to make here.

I didn't say you can't teach things quickly, I'm saying that teaching them depends on the state of the learner. That includes a lot of things like whether the person is motivated to do it, and whether they have existing bad habits or interfering beliefs.

Also, ISTM most of the things you just mentioned require external feedback for most people to learn quickly; simply giving someone a static "explanation" of the skill is not sufficient for them to actually learn to do it, or at least not very efficiently.

(Which is also part of my point about learner state-dependence. Learning skills in general requires interaction and feedback of some kind; explanations are not sufficient.)

I'm currently disentangling myself from the ill effects of combining Alexander Technique with perfectionism and desperation. I hope I'm not adding another layer of bad habits.

I agree with pjeby-- the state of the person receiving the information makes a big difference.