How to waste central thickness.

[lobotommy]

I have a question about my last game. I think I was good till move#69 but I wasn't sure how to continue. I got quite strong position in the center but how to continue? I was thinking about attack the white group on the right from below (as my opponent played on the left) but I choose to play from the center as I played in the game. Then I played 75 and it was over I think, maybe I should play something to develope the center more. Moves after 75 are so kyuish that I am embarassed that I wasted all central potential to get only few points there...
So how would you play black 69, and how to continue?

[RobertJasiek]

Count! You will notice that W wins if you take the small corner. You need to reduce W's upper side.

[Joaz Banbeck]

[admin] I thought that your post really belonged in this forum, so I moved it. You should get more responses here. -JB [/admin]


Move 27 seems strategicly inconsistent.

You have a massive wall early in the game. To get maximum benefit from a wall, you have to fight. R12 and R5 work to keep his group small and attackable, which works well with the plan for future fighting.
But with 27, you choose territory in return for letting him get influence. I'd pincer with 27.
If he runs, he will have two weak groups. If he scurries for the safety of the corner, you will get a second wall which magnifies the power of your first wall.

55: Walking into a self-hane. B13 is needed.

69: Despite the fact that white has become solid up top, you still have some tactical chances. Use your wall for attacking, not for building territory. Steal his eyespace and make him run in the shadow of your wall. Play either S8 or S9.

75: As you now observe, things are not going well for you. You are trying to use your wall to make territory. The problem is not really with 75, but with the strategic plan embarked upon many moves back.
See http://senseis.xmp.net/?DontUseThicknessToMakeTerritory

[lobotommy]

Thanks for explanation, It's really helpful. I need to be more aware of this basic stuff...

[Uberdude]

However, like all proverbs there are exceptions. In this game from the Sports Accord World Mind Games Catalin Taranu 5p of Europe had a decent start against Lee Sedol 9p of Korea, but lost because he didn't use his thickness to make territory!

http://ranka.intergofed.org/?page_id=6908

[Joaz Banbeck]

No, he lost because he played Lee Sedol.

[Bill Spight]

Several comments.

[Fedya]

It's nice to see somebody else besides me having problems with thickness.

(As a SDK, I obviously cannot in good conscience make any comments about how this game between two rather stronger players should have been played.)

[lobotommy]

Several comments.

Thanks Bill, it is much more than only several comments - it's very informative and I found a few ideas very insightful for me.
Thanks again

[Joaz Banbeck]

@Lobotommy: You are in good company. I just saw the following game on KGS. ( BTW, this game is amusing for other reasons too. I recommend following it from about move 150 to the end )