Mutual Damage/ Discussion

nachtrabe "Mutual damage in the opening is unusual."

Is that really true? It seems like Mutual Damage happens all of the time in the opening, just that it isn't as obvious that is what is happening as it is in the endgame.

Example, between Cho Hunhyun (black) and Lee Changho, 14th Asian TV Cup, round 3 final, 2002. W+3.5.

Interrupted mini-chinese opening  

is going for a mini-chinese opening (after W at 3 B at a). White, not wanting this to happen (in this case), approaches at (also preventing black from making a corner enclosure at b or c, which tends to be the followup if W pincers).

It seems like the approach at meets the definition of "mutual damage"--rather than respond to the approach at , white prevents an enclosure or framework from developing. In exchange (damaging W in return), black takes the double-kakari.

Is my understanding of mutual damage flawed in some way?

Bill: Well, the notion of mutual damage is not terribly well defined. It is usually used when each player has something more substantial to damage than a single stone -- at least a moyo.

aLegendWai: It is my little opinion. You may disagree. Mutual damage should be used somewhat like a last-ditch approach, say, in a situation if you will lose when you complete the endgame peacefully.

Hmm that doesn't sound too sensible to me, Mutual Damage is an important principle in Go, especially in yose. If you don't apply it you never get sente and lose a lot of points.

aLegendWai: Wait a moment! Maybe we refer to different situations. Anyway, try to make it clear first. I focus mainly on the issue in the endgame, and in a situation where playing elsewhere will suffer a lot. (Just like the one in the above example). I don't even consider this play unless I know I am losing (so mutual damage is the only option). The reason why I won't play it because it is complex (a lot of uncertainities during both invasions). I can't be sure if I can gain if both invasion appears to make similar damages visually. That's why I feel it is somewhat a last-ditch approach. What do you think?

Mutual damage - W is no hope  

aLegendWai: But mutual damage may not lead to winning. It is true only if you can damage more than your opponent does!

Rich|ALegendWai, please read the first sentence on the page: "...provided one can inflict equivalent damage on the opponent."

aLegendWai: Thanks for telling. But I've noticed the existence of the statement already. I repeat here as an introduction for the diagram and that case.

aLegendWai: In the above example, I think mutual damage is no hope to W unfortunately.

I would like to know if there's an easy way to judge if a mutual damage is beneficial. Now it seems the only way to find out the answer is "try it out (in mind)"!

Rich: The answer is really 'read it out'. There just isn't an easy way to do everything, I'm afraid, or we'd all be playing perfectly.

aLegendWai: Hopefully someone will invent an easy way to evaluate the value of mutual damage. It will thus save a lot of brain cells :P (joking)