Yes, I have played a blitz game once. It was on a train, in 1929.
If Tal sacrifices a piece, take it. If Petrosian sacrifices a piece, don't take it.
Memorization of variations could be even worse than playing in a tournament without looking in the books at all.
Chess cannot be taught. Chess can only be learned.
Along with my retirement from chess analytical work seems to have gone too.
You have to accustom yourself to practical study at home, you have to devote time to studies, to the history of chess, the development of chess theory, of chess culture.