Bill Spight wrote: I used to think that problem software would play against the solver, offering stubborn resistance, backtracking to play other options that the solver should be able to refute.
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a major blind spot in reading is missing the opponent's toughest replies. The reader should find those moves, too.
When I first started looking at tsumego, I couldn't figure out how to solve them on my own, because I couldn't figure out how white should reply to black's attempts. I kept making moves as white that were still in black's favor. I could only solve them when using a program that auto-replied to my every attempt.
It wasn't until I read Davies' book Tesuji, where he explained how with each move, you have to mentally switch sides and find their best move. That completely changed the game for me (pardon the pun). Now it wasn't just one problem, but many, many problems in one. (Its funny that I don't recall seeing the same explanation in he's other book, Life and Death, where it seems it would be more appropriate)
Even now, I may want to show off some novel or interesting problem to someone, but if they don't see the answer right away, I can't fully refute their incorrect attempts, because I only know the "correct" solution, and not the full problem. So they may think they've solved it differently, when they haven't yet.