Dealing with tengen openings
Posted: Mon Jul 11, 2016 5:35 pm
Recently, I played a game (as White) that opened as follows:
I couldn't figure out what to do to keep Black from getting a big moyo. I tried approaching 5 from the top, but Black wound up with most of the left side, winning when he killed my invasion. Black also had a large amount of territory in the upper right; even if my group on the left side had lived I probably would have lost badly. Now, obviously in this particular game I could have played 4 at 5 to prevent Black from getting that big moyo. To be honest, though, I've never been comfortable with diagonal fusekis either. Besides, what happens if Black opens like this:
The two remaining 4-4 points are miai, and Black gets his moyo.
I suppose the other option is to approach Black's corner with White 4 and let Black wind up with three of the four corners (especially in a game where Black opens in two different corners as opposed to a center opening), but that doesn't seem good either.
I couldn't figure out what to do to keep Black from getting a big moyo. I tried approaching 5 from the top, but Black wound up with most of the left side, winning when he killed my invasion. Black also had a large amount of territory in the upper right; even if my group on the left side had lived I probably would have lost badly. Now, obviously in this particular game I could have played 4 at 5 to prevent Black from getting that big moyo. To be honest, though, I've never been comfortable with diagonal fusekis either. Besides, what happens if Black opens like this:
The two remaining 4-4 points are miai, and Black gets his moyo.
I suppose the other option is to approach Black's corner with White 4 and let Black wind up with three of the four corners (especially in a game where Black opens in two different corners as opposed to a center opening), but that doesn't seem good either.
. Post 6.
I spent a good half hour trying to figure out what would happen if I had played at F7 or E7, but I still can't figure it out:
isn't inherently bad, but as a follow up, consider the basic joseki that runs C16, E16, D14, C17, B17, D17, B15, and then an extension by white. You may want to make it a bit narrow because of tengen. 
is problematic, looking for influence where the tengen stone is already nullifying it, and not helping the group.
is a weird direction. Black is trying to make something directly. Nothing wrong with a corner enclosure, I think, or you could even tenuki.
Black bullied white in the top left a bit to get a corner and good influence. This stems from the mistake of H16 and now white feels behind. Starting a fight here, though, is what black wants. Tengen is meant to support fighting and crazy extensions. Don't just play into it, with another weak group on the board. You could instead consider L17, slow but solid, or an approach at O17, which might invite a pincer (maybe dangerous), or maybe just grab the right side.
Black has overconcentrated himself a bit here, so maybe just support the top group, knowing that you can connect under with B6 any time. You could also play to preserve the connection with E8, since a black move there would cut it off in sente.
feels too passive. Maybe attach on top at K16? It's a tough spot. After the followup, white's group is heavy and under attack while not doing much.
What's wrong with the 3-3?
If you're going to play 
if you had the 3-3, this or J3 especially would be a good way to pressure black's group. As it is, it's pretty lackluster... just a two space extension.
Yes, locally.
is a huge mistake. Up to this point, white could have played B6 to connect underneath (look up the tesuji if you don't know it). Once white plays here, it invites black to cut white in two and a poor result is inevitable.
? 
was good. Again you achieved your strategic goal of breaking up the left side, making a decent base for your stones while B jumped into the center. No problem with opening strategy here.
. This was a big move for B, taking corner territory and making a base for his group. Do your really have to answer this move locally? That just adds insult to injury, making his move sente, and giving you an inefficient over-concentrated shape. It would be much larger, and a much more positive attitude, to make your own large play elsewhere. Approaching the upper right corner, or even invading the 3-3 point, would be huge. B would probably answer all your moves there.
that things started looking not quite right.