This kind of position (this is a made-up example) has occurred in my games recently, and on each occasion I was unable to work out how best to proceed when reviewing.
this line is normal in the case of an enclosure from a 3-4 point, but it seems out of tune when you have a wall. But I would find it hard to bring myself to play 2 defensively on the third line, and I cannot see any reasonable way to resist, either. I suppose you shouldn`t be extending on the third line from a 4-4 point wall in the first place, but it`s the kind of thing that can seem like a good idea at the time.
Would it be altogether unreasonable for Black just to keep on pushing?
unkx80: First comment. The shoulder hit exposes the weakness of being in the third line. To avoid the shoulder hit, have at a instead.
unkx80: Second comment. If the context allows, you may also consider attacking moves such as this. Of course, other attacking sequences are possible as well.
tapir: I reckon this shape is quite common, does it have a name, a SL page?
Andy: Actually Guo Juan commented a high-dan amateur game on KGS recently with exactly this kind of position. White's erasure is perfect, and you don't have a good reply to it. This means you went wrong earlier when you lost sente to allow in the first place. If instead you had got a move in at a, the game is completely different, and there's not any move elsewhere on the bottom half of the board likely to be big enough for you to not make this move. However, now that is on the board, I'd use thickness to attack, starting with the capping move . Just my 2kyu worth.
Velobici: Very interesting to hear a professional's, in this case Guo Juan's, reaction. Attacking and Defending Moyos begins with thirteen basic principles. The first one (page 2) is 1. Reduce a moyo by playing no further into it than its outer rim. From the examples in the book, White should play no deeper than b or c. There is the principle 10. Make a deep invasion only if you can end up with a secure group but the examples are 3-3 invasions under a 4-4 stone. Another principle 11. Make a deep invasion into your opponent's moyo only if there are defects that you can exploit does not appear (to me) to apply as the black stones on both the right and the left are solid.
Tamsin: Thanks for your replies! I suppose this explains why the following shape is not seen very often: