I'm wondering what would be, in terms of efficient fast improvement, the best training module between puzzle rush (fast calculation and pattern recognition strengthening) and traditional timeless puzzle solving (deep calculation strengthening) ?
Does one become better than the other at some specific elo range or vice-versa?
I usually focus on timeless puzzles as I feel like deep calculation is very important for serious OTB classical/rapid games but wonder if it would be more time efficient to train with puzzle rush instead.