[lbalazscs]

Regarding openings, there's a trade-off between chess training and chess results. Rote memorization can improve your results (if you already have good skills), but it won't improve your skills.

Learning endgames is not about blindly memorizing moves in specific positions. You learn tricks that can be used in a large number of positions. Even the seemingly very specific positions can be mirrored left-right (not to mention black-white).