Practice Doesn't Make Perfect

I don't know any computer scientist who looks at the code he wrote a few years ago and won't think of mich better ways to do things.

What is that if it's not an increase in skills due to practice?

As a generalisation (take with pinch of salt), the classic Japanese method does not have lots of explanation - teacher demonstrates, teacher works with student, can be quite hands on with corrections to body posture etc, but not typically lots of explanation. There are also exercises shown to develop body conditioning, and awareness. These include exercises such as standing, or slow deep walking, which initially are not obvious as to what is happening and why. The students who take these on trust and go off and do them in their own time are the ones who make progress. There is also quite a lot of focus on "mitori keiko" - training by watching, so training people to become more observant about what they are seeing and then be able to take that understanding or images and apply it to their own training.

Western students tend to require more explanation. They ask "why should I do this (apparently boring) exercise?". There can be a tendency to pursue acquisition of technique rather than fundamentals. They are less likely to take things on trust and work it out for themselves. Of course there are plenty of great Western practitioners and plenty of poor Japanese ones.

As a teacher I found my tendency was to try and explain too much. I find I get better results when working with people and making them feel things. I have seen my main teacher in Japan work on someone for 5-10 minutes and extract out them very signficiant improvement in that time - and he has done that to me. He can give people a taste for a new level and inspire them, but the challenge then is to go off and do the personal work to really own that new level or those insites. That is a goal for me to be able to do the same for my students.

My main teacher in UK was a contemporary dancer for his working life, and with his contacts etc has inspired quite a few dancers to come to the dojo. It has been interesting for me to work with them over the years, and understand how varied dance training can be. Some dance training seems to be more about the externals - make a move look a certain way, without worrying about the internal mechanics of the body. And yet of course other training is at a deeper level, training awareness. I realised over time the distinct difference between someone who is very flexible, and yet can feel relatively "hard" - just due to their background and the focus of their training to that point.

I found Josh Waitzkin's book on learning about his experiences as a chess prodigy and then learning and competing at Taiji Push Hands to highest levels. He writes about deepening his awareness, and also the sheer time spent in practising and analysing his techniques and failures etc.

Lets take example with Sudoku: if you know the basics(marking candidates and eliminating rows/columns), you can solve easy puzzles with practice only, but you'll be stuck solving mid-level puzzles. Mid-level puzzles require intuitive understanding of column-row exclusion(where X number candidates in a block are exclusively on one row or column they exclude X from entire row or column), but aren't sufficient for solving high-level puzzles. High-level play requires knowledge of subsets, X-wings,XY chains,coloring, etc to solve the hardest puzzles(and practicing doesn't help, it requires intuitive understanding to find such patterns).

I have never seen it put better.

The Soviet Union had a stranglehold on chess for almost 70 years until its collapse in the nineties. Then information fled with grandmasters to the west and the present bloom in talent began. Westerners began to regularly defeat soviet players. An Indian, then a Norwegian became world champion. Before then, it was a small miracle to defeat a soviet player. Reason? Information.

My personal experience: I played chess with a lot of frustration and little improvement for over a decade until I began reading 'honest' books written by Soviet trainers. That was I began to see progress.I gained approximately 200 elo in one year.(I would estimate that 90% of chess books for intermediate players are crap, some of these are deliberately misleading hence the 'honest' term)

Genetics and hard work are vastly inferior to information