Tapir: I am white and this happened several times to me already in the last week. The idea behind and is obviously to leave less invasion points.
unkx80: The sanrensei is influence-orientated but and is played low. These moves to not coordinate well with the sanrensei, and are not optimal for sanrensei framework development. Therefore, you can just play normally and not worry so much about invading the sanrensei.
Tapir: My opponent tried this in the game. Can this be good for black? (Black can't resist by playing a because the ladder after favours white.) Though it ends in gote for white.
Herman: Actually, the ladder isn't important...
Of course white can connect under at a instead of , but connecting on the first line in the opening is not what white was hoping for.
Which means this is probably white's best option. Now white must still be careful to not end up with a J-Group.
I think the descent in the original diagram is the problem. White can play like this, which is an acceptable result (corner territory + sente)
Tapir: Ouch, and thank you. Not seeing loose ladders should not happen anymore, but -
Herman: :-) Oh, and as to the original question: I think the end result (where I assume white connects under) is perhaps slightly better for white. Both and are mistakes, so they sort of cancel out getting, but to connect while also making corner territory feels slightly better for white.
tapir: Please forget my silly play for now. How should any serious white respond?
Andy: Something like this for white maybe? With , low, presumably for territory, white can take the influence instead and all black's stones wind up on the same side of the board. On the other hand, if white is going to come in at 3-3 right away, white needs to ensure that () end up as inefficient plays.
tapir: I would not feel happy to play against 60 points of probable territory. Even if there is some sabaki potential (I would try at c) I doubt white will ever have the time to try this as black has sente and will invade reduce most prospects white has easily. I take Black here. Sure black has territory and is strong - white has not more influence imo but is rather thin compared to black. Just playing all a sequences now, seems to be enough for black.
MrTenuki: Tapir, do you mean something like this?
This actually looks quite good for white - I would continue with 'A', and by the time that poor black invasion stone is living, white should have built up enough thickness that using the word 'secure' for the black territory would only invite laughter and ridicule. And black may well make a mistake somewhere, after which driving white straight into the left side might be the only remaining option to live.
Still, if it doesn't suit your liking, then there exist other ways to answer the 3-3 point invasion:
Now it's even harder for black to find the right spot to do something about the huge white moyo. - Andre Engels
tapir: Hmm, I wouldn't play out the 3-3 invasions now and then wonder about the moyo in the middle. And black can effectively choose the side to make the ponnuki after the double hane, and surely would not allow having the upper and the lower side of white work together that nicely. Also starting at the d points, keeping the 3-3 for later seems efficient to me.
BobWhoosta: I totally agree with Andre here, black is flat and uninteresting. I've played this kind of setup with white many many times, and I win far more often than I lose. Black is ignoring many principles of good go, and will most likely need to make himself two or even three weak groups to "reduce" white effectively. White just needs to understand the value of his attack vs. tenuki.