We're seeing a white 5-3 more often these days, but this one is black and it's an interesting plan. To me, black - - has a feeling of declaring "my endgame is much better than yours." But black is a pro and wins this game, so it goes to show how much flexibility there is in go.

Good reason to start the shimari from 5-3 point: kyu players (and even some dan players) afraid of taisha joseki, so they never play kakari So, you can make shimari later

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