>>127167373Frankly, you sounds like you've never played an instrument seriously.
>You need as little teacher, as little note-sheets, and as little music theory as possibleThis is a vague and nonsensical rule. In the end, it entirely depends on what you're trying to achieve. If your goal is to have a holistic approach to music, something that was actually more common in the past, you should be doing everything: playing, listening, improvising, reading, writing, analyzing, etc. The idea that music theory is somehow a modern, academic obstruction completely ignores that composers and performers in the past often had a very deep, practical understanding of theory, because it was inseparable from how music was made.
On the other hand, if you're content to playing pieces as simple as Bach's Prelude in C major or Satie's Gymnopedies, and not going up several levels, you can start and end with those, and do nothing else.
>something very profane and not sacred or hard to understand at allNobody is claiming it's sacred or mystical. The reason people seek good technique and solid foundations is not because music is "hard to understand", but because it's hard to do well. You can absolutely "just move your fingers in some patterns", but do it the wrong way, and you'll either sound bad or literally hurt yourself. This isn't theoretical or metaphysical or anything; it's purely physical. Your body has limitations, and bad habits compound over time.
>"wrong" techniqueNobody is implying piano technique is some rigid monolith where there's only one correct way to move your hands, but that doesn't mean there isn't such a thing as doing it poorly. There are multiple valid schools of piano technique, and professionals spend years refining their approach. All of those have informed principles behind them. It's not just finger-wiggling. The point is about building a reliable, sustainable, expressive technique that allows you to make music without pain, limitations, or frustration.