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The mistakes I make
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Author:  mongus [ Mon Oct 17, 2016 1:53 pm ]
Post subject:  Re: The mistakes I make

Ah yes, true. That would have been better. It's just the aforementioned advice was more pertinent, as I had that position twice in the game. I actually thought I was being clever, thinking if my opponent did take the stone it was ok because I could just cover it easily.


Click Here To Show Diagram Code
[go]$$W
$$ | . . . . . . . . . . . .
$$ | . . O , . . . . . , . .
$$ | . . O X . . . . . . . .
$$ | . O X 1 2 . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . . . . . . . . . . .
$$ | . . . X . . . . . , . .
$$ | . . . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ +------------------------[/go]


So, no point wasting a move on it.

Reflecting on this, I can see that this sort of mindset actually gets me into trouble an awful lot. It this game it actually did. My opponent was able to use the weakness I had left in the bottom right to ensure his fragile central group was safe. Had I not left that weakness I would have been in a much stronger position.

It is very hard to know the difference between a strong move and a slow move. Perhaps it is one of those eternal Go dilemmas.

Author:  Bill Spight [ Thu Oct 20, 2016 8:29 am ]
Post subject:  Re: The mistakes I make

mongus wrote:
I actually thought I was being clever, thinking if my opponent did take the stone it was ok because I could just cover it easily.


Click Here To Show Diagram Code
[go]$$W
$$ | . . . . . . . . . . . .
$$ | . . O , . . . . . , . .
$$ | . . O X . . . . . . . .
$$ | . O X 1 2 . . . . . . .
$$ | . a O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . . b . . . . . . . .
$$ | . . . X . . . . . , . .
$$ | . . . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ +------------------------[/go]


So, no point wasting a move on it.

Reflecting on this, I can see that this sort of mindset actually gets me into trouble an awful lot.


Actually, your basic argument is sound. The trouble is, you did not consider the effect of local weaknesses, indicated at "a" and "b".

Click Here To Show Diagram Code
[go]$$W
$$ | . . . . . . . . . . . .
$$ | . . O , . . . . . , . .
$$ | . . O X . . . . . . . .
$$ | . O X 1 2 . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . , . .
$$ | . O X X . . . . . . . .
$$ | . O . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ +------------------------[/go]


In this case, without those weaknesses, it makes much more sense for Black not to connect at 1.

Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . . . . . .
$$ | . . O , . . . . . , . .
$$ | . b 2 a . . . . . . . .
$$ | . O X 1 . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . . . .
$$ | . . O X . . . . . , . .
$$ | . O X X . . . . . . . .
$$ | . O . . . . . . . . . .
$$ | . . . . . . . . . . . .
$$ +------------------------[/go]


But even in this situation, the culprit is the hanging connection at "a". The solid connection, :b1:, threatens "b" but leaves no weakness behind if White answers with :w2:.

Quote:
It this game it actually did. My opponent was able to use the weakness I had left in the bottom right to ensure his fragile central group was safe. Had I not left that weakness I would have been in a much stronger position.


In that case, too, it is a problem of your own making.

Click Here To Show Diagram Code
[go]$$Bcm26
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . . . . . . . . . . . . |
$$ | . . . O . . . . . X . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . X . . . . . X . X . |
$$ | . . . . . . . X . O . X . O 1 2 B O O |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


:b26: threatens to cut the White in two, but it is an overplay. :w27: puts the question, do you save :b26: or :bc:?

Quote:
It is very hard to know the difference between a strong move and a slow move. Perhaps it is one of those eternal Go dilemmas.


As you get stronger your judgement about that, and many other things, will improve. :D

Author:  mongus [ Sat Oct 22, 2016 12:08 pm ]
Post subject:  Re: The mistakes I make

Here's a mistake I'm surprised I haven't encountered before. Then I made it twice in last nights game.

I'm White. In the end game I want to eke out every last point so I decide to play at a :

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O . . . |
$$ . X . X O . . . . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X a |
$$ . . . . . . . . . |[/go]


Of course this does not go well at all :

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X O O O . . . |
$$ . X . X O . . . . |
$$ . . . X X O O 4 . |
$$ . . . . X X X O . |
$$ . . . . . X O O 3 |
$$ . . . . . X X X 1 |
$$ . . . . . . . . 2 |[/go]


Ug. It's a good reminder to always be on the look out for weaknesses before moving.

Author:  Uberdude [ Sat Oct 22, 2016 12:38 pm ]
Post subject:  Re: The mistakes I make

mongus, you are right you should check for weaknesses before moving; can you find what Black can do in the first diagram if it's his move?

Edit: don't scroll down if you don't want to see the answer.

Author:  dfan [ Sat Oct 22, 2016 12:39 pm ]
Post subject:  Re: The mistakes I make

Ah yes, the "second-line chomp." This will not be the last time you encounter it :) It's often more valuable than it seems to have three stones on the second line rather than two for this reason; you have time to capture the cutting stone when Black makes that cut. You will also often see first-line throw-ins to set this up.

[Edited to remove the answer to Uberdude's Socratic question, which I accidentally wrote before he asked it.]

Author:  mongus [ Sat Oct 22, 2016 12:56 pm ]
Post subject:  Re: The mistakes I make

Just spotted another weakness :

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O . . . |
$$ . X . X O 2 1 . . |
$$ . . . X X O O 3 . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


:oops:

Author:  mongus [ Sat Oct 22, 2016 1:00 pm ]
Post subject:  Re: The mistakes I make

dfan wrote:
Ah yes, the "second-line chomp."


So it has a name. That's interesting, so the thing to look out for is having two stones along the second line?

Author:  mongus [ Sat Oct 22, 2016 1:10 pm ]
Post subject:  Re: The mistakes I make

I think this is another option for black. Is this what you mean by the throw in?

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O . . . |
$$ . X . X O . . . . |
$$ . . . X X O O 3 5 |
$$ . . . . X X X O 2 |
$$ . . . . . X O O 1 |
$$ . . . . . X X X 4 |
$$ . . . . . . . . . |[/go]

Author:  dfan [ Sat Oct 22, 2016 4:11 pm ]
Post subject:  Re: The mistakes I make

mongus wrote:
dfan wrote:
Ah yes, the "second-line chomp."

So it has a name.

Oh, it's just the name I give it. I don't think it has a real name.

Quote:
That's interesting, so the thing to look out for is having two stones along the second line?

When Black cuts, his stone will have two liberties, and White will go first. So the thing to look for is for the White stones being cut to have only one liberty (after being cut). All of these three moves result in a successful capture:

Click Here To Show Diagram Code
[go]$$B
$$ . O . . . . .
$$ . X O O 1 . |
$$ . . X X O . |
$$ . . . . X . |
$$ . . . . . . |[/go]

Click Here To Show Diagram Code
[go]$$B
$$ . O . . . . .
$$ . X O O 1 . |
$$ . . X X O . |
$$ . . . X O O |
$$ . . . . X X |
$$ . . . . . . |[/go]

Click Here To Show Diagram Code
[go]$$B
$$ . O . . . . .
$$ . X O O 1 . |
$$ . . X X O . |
$$ . . . X O O |
$$ . . . . X O |
$$ . . . . X X |
$$ . . . . . . |[/go]


What I meant about throw-ins is that this doesn't work:
Click Here To Show Diagram Code
[go]$$W White has two liberties
$$ . O . . . . .
$$ . X O O 4 . |
$$ . . X X O . |
$$ . . . X O . |
$$ . . . X O 3 |
$$ . . . . X 1 |
$$ . . . . X 2 |
$$ . . . . . . |[/go]

but this does:
Click Here To Show Diagram Code
[go]$$W :w5: at :w2:
$$ . O . . . . .
$$ . X O O 6 . |
$$ . . X X O . |
$$ . . . X O 3 |
$$ . . . X O 2 |
$$ . . . . X 1 |
$$ . . . . X 4 |
$$ . . . . . . |[/go]

Obviously White would not actually play :w5: at :w2: in a real game!

By the way, you should still try to answer Uberdude's question. (I had accidentally told you the answer in a comment I made at the same time as his question, but I have deleted my spoiler.)

Author:  mongus [ Sun Oct 23, 2016 4:49 am ]
Post subject:  Re: The mistakes I make

Thanks, that throw in is pretty devastating!

dfan wrote:
Oh, it's just the name I give it. I don't think it has a real name.


It's a good name :-)

dfan wrote:
By the way, you should still try to answer Uberdude's question. (I had accidentally told you the answer in a comment I made at the same time as his question, but I have deleted my spoiler.)


I came up with a couple of possibilities above. Are there other options?

Author:  dfan [ Sun Oct 23, 2016 5:13 am ]
Post subject:  Re: The mistakes I make

mongus wrote:
dfan wrote:
By the way, you should still try to answer Uberdude's question. (I had accidentally told you the answer in a comment I made at the same time as his question, but I have deleted my spoiler.)

I came up with a couple of possibilities above. Are there other options?

Oh, so you did! I missed it. I was thinking of this, which is easier to find in a game:

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O 1 . . |
$$ . X . X O 2 . . . |
$$ . . . X X O O 3 . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]

But your move works too.

Author:  mongus [ Sun Oct 23, 2016 12:22 pm ]
Post subject:  Re: The mistakes I make

Couldn't White ensure survival with the following :

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O 1 2 . |
$$ . X . X O 3 . . . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


Then :


Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . 2 X O . |
$$ . X . X . X 1 . 3 |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]



I think that shape is alive?

Author:  dfan [ Sun Oct 23, 2016 1:14 pm ]
Post subject:  Re: The mistakes I make

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O 1 2 . |
$$ . X . X O . 3 . . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]

Author:  Fedya [ Sun Oct 23, 2016 1:18 pm ]
Post subject:  Re: The mistakes I make

mongus wrote:
Couldn't White ensure survival with the following :

Click Here To Show Diagram Code
[go]$$B
$$ ------------------+
$$ . . X O O O 1 2 . |
$$ . X . X O 3 . . . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


Then :


Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . 2 X O . |
$$ . X . X . X 1 . 3 |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]



I think that shape is alive?


Then :


Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X 1 2 . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


I like Dfan's variation better.

Author:  Bill Spight [ Sun Oct 23, 2016 2:26 pm ]
Post subject:  Re: The mistakes I make

Fedya wrote:
Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X 1 2 . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


I like Dfan's variation better.


Oh, yours looks like fun, though. :D

Author:  Bill Spight [ Sun Oct 23, 2016 2:30 pm ]
Post subject:  Re: The mistakes I make

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . 1 . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


Just to cross the eyes and dot the teas. What now?

Author:  mongus [ Mon Oct 24, 2016 5:48 am ]
Post subject:  Re: The mistakes I make

Ah yes. Thanks. I guess life would only be assured if you were playing against me!



Bill Spight wrote:
Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . 1 . |
$$ . . . X X O O . . |
$$ . . . . X X X O . |
$$ . . . . . X O O . |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


Just to cross the eyes and dot the teas. What now?



Hmm...

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . O 4 |
$$ . . . X X O O 3 2 |
$$ . . . . X X X O . |
$$ . . . . . X O O 1 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


or

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . O 4 |
$$ . . . X X O O 1 . |
$$ . . . . X X X O 3 |
$$ . . . . . X O O 2 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


or

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . O . |
$$ . . . X X O O . 1 |
$$ . . . . X X X O . |
$$ . . . . . X O O 2 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]



Either way, white is dead.

Author:  dfan [ Mon Oct 24, 2016 6:06 am ]
Post subject:  Re: The mistakes I make

mongus wrote:
Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . O 4 |
$$ . . . X X O O 3 2 |
$$ . . . . X X X O . |
$$ . . . . . X O O 1 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]

Does White have an alternative on move 3?

Quote:
Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X . O . |
$$ . . . X X O O . 1 |
$$ . . . . X X X O . |
$$ . . . . . X O O 2 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]


and now what does White play?

Author:  mongus [ Mon Oct 24, 2016 6:17 am ]
Post subject:  Re: The mistakes I make

Ah

Click Here To Show Diagram Code
[go]$$W
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X 3 O . |
$$ . . . X X O O . 1 |
$$ . . . . X X X O 5 |
$$ . . . . . X O O 2 |
$$ . . . . . X X X 4 |
$$ . . . . . . . . . |[/go]



White lives.

Author:  ez4u [ Mon Oct 24, 2016 6:18 am ]
Post subject:  Re: The mistakes I make

In Bill's diagram it is Black to play not White. If Black plays tenuki, White lives...
Click Here To Show Diagram Code
[go]$$Wc
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X 3 O . |
$$ . . . X X O O . 1 |
$$ . . . . X X X O . |
$$ . . . . . X O O 2 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]

Click Here To Show Diagram Code
[go]$$Wc
$$ ------------------+
$$ . . X . . . X O . |
$$ . X . X . X 1 O 3 |
$$ . . . X X O O 5 2 |
$$ . . . . X X X O . |
$$ . . . . . X O O 4 |
$$ . . . . . X X X . |
$$ . . . . . . . . . |[/go]

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