I played a game recently where my opponent built up a wall so I approach the open corner to break it up, this lead to a pretty strange variation which I am fairly sure isn’t joseki, but the result I got seemed ok. The question is, should I have just split instead?
Here is the game in question, https://online-go.com/game/5158631, the approach is move 30.
Thanks.
I’m only ~9k, but I would like to take a guess and see what stronger players think. I like the splitting move at L3 instead of the approach of W30. That way, Black is left with no good follow up: no matter which side Black approaches from you can make a two space extension. If Black extends from his wall he will be over-concentrated and you can still approach the corner. If Black extends from the corner, his wall will become useless and the corner will still be open.
After white plays the corner approach W30, Black is able to simultaneously extend from his wall and attack White with the pincer, which seems worse than if White played at L3.
I think Black’s pincer in game was too soft though and should have been at M3, though I am less confident about this. Since Black has such a large wall, a 5 space extension seems warranted and puts more pressure on white.
The issue with the split is that if I got pushed into the wall, there is quite an easy way to remove my eyes, meaning that my group is weak and right next to my opponent’s strength. On the closeness of the pincer thing, I think my opponent close the right one, as if she chose the closer one then my attach would be more effective, but I don’t really know…
Since White can easily run to the center and Black’s wall does not have two eyes yet, White doesn’t seem that weak to me, though I see your point.
Have you thought about approaching on the other side? I don’t like making a small group on the bottom when you could just build something bigger on the right. If you play lightly on the right side (just approach and ignore when he answers, unless he pincers or attaches), you can come back and play around G6 to split Black from the top and limit his growth.
Locally, I would have made the approach at O3 too, followed by either your attachment at L4 or a counter pincer. I wouldn’t use the sequence in the game as a reference though, as black plays atari too often.
White L3 - black N3 creates a weak white group and will let black build on the bottom right. I don’t think you can really hope to pressure black’s lower left group.
Even though the lower right is still open, my preference for move 30 would be to play on the top left, for example at B16 or C12, as it will shift the balance of power in that area.