Tapir: Maybe white should play lightly now, and gain something with moves like a next.
Tapir: But don't people say, that only the enclosure with the simple knight's jump at a instead of the large one and a kosumi is safe from the 3-3 invasion? However what may happen now after white a looks complicated (possibly crosscut). In the game (i was black) I wasn't confident whether the result favours me at all. Basically White got and in sente - Black was strong before and only defended territory. While the White group was much stronger after the exchange, and endgamewise and are large as well.
xela: Do they really say that? I haven't heard it before. Anyway, comparing these three pages -- 4435 enclosure, FightingKoTheBook#diag1, 3-3 Point Method Dictionary -- it looks as though the result depends a lot on context. I'm guessing now that might have been better at b. It would be nice to see more of the board, to judge how upset white will be if the stones suffer.