So take someone like young Paul Morphy, there is no stockfish and no KID, no Dragon, no 1953 or My System, and yet he got to a level where he was playing several people blindfold etc. So what was the routine? Sit down with a strong player and throw pieces around? Did he have a notebook and write positions and games in? What old books were around then?
Books and columns never explain HOW to practice. Like for example I was reading Alekhine’s best games collection, and Alekhine writes to the effect of: “I played with a classmate during classes, then when teacher took the board away we played without a board”... How did he get to the level where he could play blindfold... and so did his friend? What is the training regimen for that? I peaked at 2120 so far and can’t even comprehend how people play blindfold at all.