Yesterday I was watching an IGS game. Jirohachi 7d was playing White giving 3 handicap stones. He had just lost a ko and executed on his ko threat to kill a big group. He only caught a small part of it and the big tail was alive.

At move 133 a spectator started asking about J11, as this would kill the group according to him. Obviously this was not true, since Black could make two eyes at the right side. I wasn't logged in so I could not reply. But then I saw it ... The comments kept coming in but nobody saw it. Even Jirohachi 7d did not see it. I checked it a few times to be sure. I felt like that lone spectator knowing who is the bad guy. "There there, behind you!"

Go to 133. Do you see it?

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Then we agree: it's not a picknick ko for White but I'm not sure both players knew all that and just left it as aji.

I tell you, reading this discussion makes me think that maybe Ed Lee is right. No coordinates, please.

There are ko positions here like I have never seen before. Very interesting.

It is hard for me to think that Jirohachi did not see the ko, given the play leading up to :w133:. But I think that he saw that it was an approach ko with Black to take first, and thought (erroneously, IMO) that taking some stones in sente was best.



Edited some variations.

Edit: I am not at all sure about the W O-10, B N-09 exchanges. This is an unusual ko situation, which I will be studying some more.

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So we should call this is an approach-ko ko, rather than an approach-move ko?
(W must win the first ko in order to earn the opportunity to start the killing ko.)