Guksu 2005 Game 3
Corentin: this game was audio-commented up to move 72 by Jiang Mingjiu Chinese 9p on Sunday Feb 20, 2005 in KGS (room>lesson>Ing's Goe Internet Class). Scribe wrote down the professional's main points. (URL to game record with comments appears on Scribe's page.) He spent about 50 minutes on this game, of which at least 30 minutes were on the fuseki. I don't remember any comments being made on this move , but my memory is slack... As for the 'overconcentrated move ' (see 2 diagrams below), although someone asked why it was played, he didn't comment it. He gave some variations (unacceptable for either W or B) of the fight that starts with (see 3 diagrams below, move ).
Alex Weldon: Given than White invades the shimari with in the next diagram, perhaps was played in anticipation of this, allowing B to respond at in the next diagram. It also has the double purpose of aiming at and in the next diagram to flatten out White's position and reduce her thickness. It still looks overconcentrated to me and I wouldn't have thought of playing it, but it does at least seem to be a multipurpose play.
Alex Weldon: Hmm, my way of looking at it is that is making territory while attacking, which is not nearly as bad as using thickness to make territory directly. Black is fairly strong on both sides, so he isn't really violating the principle of attacking from the weaker side, and territory made on either side would be close to thickness. I suppose that when one is thick on both sides, the normal way to attack is some sort of capping play, but I guess Black read out here that he couldn't kill or gain enough profit like that. Also, since the resulting sequence builds up power facing the lower side (which you later refer to as "central potential" rather than thickness) as well as territory, Black may already be planning his later sequence beginning at move 113.