Life In 19x19

BTW, Fedya, why didn't you play the hane and connect in the corner?

I was thinking about the hane followed by the descent, but realized that failed to a Black move on the 2-2 point.

Yeah, hane (on the second line) and descent (to the first line) is useful much less often than one thinks at first, largely because you are not only leaving a cutting point (on the second line, where it's easy to make captures) but also leaving yourself with a small number of liberties. It occasionally is the right move in special circumstances but it generally shouldn't be your first instinct. (Stronger players, please correct me )

dfan wrote:Yeah, hane (on the second line) and descent (to the first line) is useful much less often than one thinks at first, largely because you are not only leaving a cutting point (on the second line, where it's easy to make captures) but also leaving yourself with a small number of liberties. It occasionally is the right move in special circumstances but it generally shouldn't be your first instinct. (Stronger players, please correct me )

It's sometimes good to increase eyespace to allow living where you otherwise couldn't. I tried making an example, but I saw that it was a bit wrong.

Fedya wrote:

BTW, Fedya, why didn't you play the hane and connect in the corner?

I was thinking about the hane followed by the descent, but realized that failed to a Black move on the 2-2 point.

I was asking about this hane and connect.

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[go]$$W
$$ ---------------
$$ . . . . . . . |
$$ . . 2 1 3 . . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X . . |
$$ . . . X . . . |[/go]

But while we are at it, how does Black respond to in this sequence?

Click Here To Show Diagram Code

[go]$$W
$$ ---------------
$$ . . . . . 5 . |
$$ . . . X O 4 . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X 1 3 |
$$ . . . X . 2 . |[/go]

Example for Kirby:

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[go]$$B B to live (ko)
$$ -------------------------
$$ . . . . . . . . . . |
$$ . . O . O X . . . . |
$$ . . . . O . . X X . |
$$ . . . . . O O . O . |
$$ . . . . . . . O . . |
$$ . . . . . . . . O . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$[/go]

I was asking about this hane and connect.

I didn't think about the hane and connect. When I saw that the hane and descend didn't work, I stopped thinking about the hane.

Fedya wrote:

I was asking about this hane and connect.

I didn't think about the hane and connect. When I saw that the hane and descend didn't work, I stopped thinking about the hane.

So you saw this:

Click Here To Show Diagram Code

[go]$$W
$$ ---------------
$$ . . . 3 . . . |
$$ . . 2 1 . 4 . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X . . |
$$ . . . X . . . |[/go]

and said, No good, right?

What about this?

Click Here To Show Diagram Code

[go]$$W
$$ ---------------
$$ . . . 3 . . . |
$$ . . 2 1 5 4 . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X . . |
$$ . . . X . . . |[/go]

Bill Spight wrote:

Fedya wrote:

BTW, Fedya, why didn't you play the hane and connect in the corner?

But while we are at it, how does Black respond to in this sequence?

$$W
$$ ---------------
$$ . . . . . 5 . |
$$ . . . X O 4 . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X 1 3 |
$$ . . . X . 2 . |

Click Here To Show Diagram Code

[go]$$W
$$ ---------------
$$ . . . . . 5 . |
$$ . . . X O 4 . |
$$ . O . X O . . |
$$ O . . X O . . |
$$ X X . . X 1 3 |
$$ . . . X . 2 . |[/go]

Come to think of it, I can't find anything that doesn't lead to a ko at best for Black. For some reason I thought I had looked at that variation, but I hadn't.

Bill Spight suggested:

$$Wcm52 White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . f . . . . . . . . . . . . . . . . |
$$ | . . X O . X . O . . . . . O . . . . . |
$$ | . . X O . . . . . , O O O . . X . . . |
$$ | . . X O . . . . . . . X X X . . . . . |
$$ | . X X O . . . . . g . . . . . X . e . |
$$ | . O O O . . . . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . . . . . . . . . . . |
$$ | . . O O . . . . . , . . . . c , b . . |
$$ | . X . . . . . . . . . . . d . . . . . |
$$ | . . . X . . . . . . . a . . B . B . . |
$$ | . . . . . . . . . . . . . B . . . . . |
$$ | . . . . . . . . . . . . W W W . W . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . X , . O . . . X . . . X . X . W . |
$$ | . . . O . . . . O . X . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Wcm52 White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . f . . . . . . . . . . . . . . . . |
$$ | . . X O . X . O . . . . . O . . . . . |
$$ | . . X O . . . . . , O O O . . X . . . |
$$ | . . X O . . . . . . . X X X . . . . . |
$$ | . X X O . . . . . g . . . . . X . e . |
$$ | . O O O . . . . . . . . . . . . . . . |
$$ | . O X X . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . . . . . . . . . . . |
$$ | . . O O . . . . . , . . . . c , b . . |
$$ | . X . . . . . . . . . . . d . . . . . |
$$ | . . . X . . . . . . . a . . B . B . . |
$$ | . . . . . . . . . . . . . B . . . . . |
$$ | . . . . . . . . . . . . W W W . W . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . X , . O . . . X . . . X . X . W . |
$$ | . . . O . . . . O . X . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

"g" (K14) is one I should have spotted. "a" I would have rejected because of the push and cut, and don't know that I would have found anything like Bill's way of making it viable. I think b-e are all the sort of thing I'd look at and talk myself out of because strong players would criticize me for playing much too deep an invasion.

Click Here To Show Diagram Code

[go]$$Wcm62 Move 2
$$ ---------------------------------------
$$ | . . . . . . . . . . X . X O O . . . . |
$$ | . X . X O . . . . . . X X O . O . . . |
$$ | . . X O . O O O X X X X O O . O . . . |
$$ | . . X O . . . X O O O O O X O O O X . |
$$ | . X O . . . . X X X X O X X . O X . . |
$$ | . X O . . . O . . X . X . . . O X . . |
$$ | . . O . . . O . O O X X X . . . . X . |
$$ | . . . . . . . . . X O O . . O O X . . |
$$ | . . . . . . . X . X X O O O . . . . . |
$$ | . . X , . . . . . , O X X O X X X . . |
$$ | . . . X . . X O . X X X O X O O X . . |
$$ | . . X O . . X O . O O X O X . O O O . |
$$ | . . X O X . X X O . . O O O . . . . . |
$$ | . X O O O . . . X O . . . O O . . . . |
$$ | . X O . O X X . X O . . . O X O O . . |
$$ | . . X O O . O O O X X . O X . X X . . |
$$ | . . X X O . O X X X . O . X . X . . . |
$$ | . . . . X X O . . . 1 . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I suggested this kosumi as something to play around with even though, as Knotwilg points out, it has no direct effect on the liberties of either side. There are lessons here that I have not had time to write about, so let me get started.

The first lesson is simple. White threatens to connect to his threatened group, saving it and killing the Black group in one blow.

Click Here To Show Diagram Code

[go]$$Wcm62 Kosumi and connection
$$ ---------------------------------------
$$ | . . . . . . . . . . X . X O O . . . . |
$$ | . X . X O . . . . . . X X O . O . . . |
$$ | . . X O . O O O X X X X O O . O . . . |
$$ | . . X O . . . X O O O O O X O O O X . |
$$ | . X O . . . . X X X X O X X . O X . . |
$$ | . X O . . . O . . X . X . . . O X . . |
$$ | . . O . . . O . O O X X X . . . . X . |
$$ | . . . . . . . . . X O O . . O O X . . |
$$ | . . . . . . . X . X X O O O . . . . . |
$$ | . . X , . . . . . , O X X O X X X . . |
$$ | . . . X . . X O . X X X O X O O X . . |
$$ | . . X O . . X O . O O X O X . O O O . |
$$ | . . X O X . X X O . . O O O . . . . . |
$$ | . X O O O . . . X O . . . O O . . . . |
$$ | . X O . O X X . X O . . . O X O O . . |
$$ | . . X O O . O O O X X . O X . X X . . |
$$ | . . X X O . O X X X . O . X . X . . . |
$$ | . . . . X X O . . . 1 . . . . . . . . |
$$ | . . . . . . . . . 3 . . . . . . . . . |
$$ ---------------------------------------[/go]

This is one of the basics that Fedya should learn if he does not already know it.

Lesson number 2:

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[go]$$Wcm62 White gains a liberty
$$ ---------------------------------------
$$ | . . . . . . . . . . X . X O O . . . . |
$$ | . X . X O . . . . . . X X O . O . . . |
$$ | . . X O . O O O X X X X O O . O . . . |
$$ | . . X O . . . X O O O O O X O O O X . |
$$ | . X O . . . . X X X X O X X . O X . . |
$$ | . X O . . . O . . X . X . . . O X . . |
$$ | . . O . . . O . O O X X X . . . . X . |
$$ | . . . . . . . . . X O O . . O O X . . |
$$ | . . . . . . . X . X X O O O . . . . . |
$$ | . . X , . . . . . , O X X O X X X . . |
$$ | . . . X . . X O . X X X O X O O X . . |
$$ | . . X O . . X O . O O X O X . O O O . |
$$ | . . X O X . X X O . . O O O . . . . . |
$$ | . X O O O . . . X O . . . O O . . . . |
$$ | . X O . O X X . X O . . . O X O O . . |
$$ | . . X O O . O O O X X . O X . X X . . |
$$ | . . X X O . O X X X . O . X . X . . . |
$$ | . . . . X X O 2 . . 1 . . . . . . . . |
$$ | . . . . . . 3 . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

With this exchange Black prevents the connection with sente, but, while the dame count remains the same for each player, White has gained a liberty. This gain of a liberty is another one of those basics that SDKs should know or learn. To illustrate the gain of a liberty, let us start filling the dame.

Click Here To Show Diagram Code

[go]$$Bc Filling the dame
$$ ---------------------------------------
$$ | . . . . . . . . . . X . X O O . . . . |
$$ | . X . X O . . . . . . X X O . O . . . |
$$ | . . X O . O O O X X X X O O . O . . . |
$$ | . . X O . . . X O O O O O X O O O X . |
$$ | . X O . . . . X X X X O X X . O X . . |
$$ | . X O . . . O . . X . X . . . O X . . |
$$ | . . O . . . O . O O X X X . . . . X . |
$$ | . . . . . . . . . X O O . . O O X . . |
$$ | . . . . . . . X . X X O O O . . . . . |
$$ | . . X , . . . . . , O X X O X X X . . |
$$ | . . . X . . X O . X X X O X O O X . . |
$$ | . . X O 3 . X O . O O X O X . O O O . |
$$ | . . X O X . X X O . . O O O . . . . . |
$$ | . X O O O 5 . . X O . . . O O . . . . |
$$ | . X O . O X X 7 X O 6 . . O X O O . . |
$$ | . . X O O 9 O O O X X 2 O X . X X . . |
$$ | . . X X O 8 O X X X . O . X . X . . . |
$$ | . . . 0 X X O X . 4 O . . . . . . . . |
$$ | . . . . . a O 1 . . . . . . . . . . . |
$$ ---------------------------------------[/go]

takes away a White dame, leaving the dame count at 6 to 5, so that Black is apparently one liberty ahead. But White throws in just in the nick of time, so that Black must spend two moves to capture it before filling the dame at "a". Even with Black to play, White has 4 liberties to 3 for Black, and wins the semeai. Note that White gains this liberty only because he has an eye. If "a" were the last White dame to be filled, doing so would capture the White stones and Black would not have to worry about putting himself in atari. But the eye is the last dame to be filled, so the first line descent gains a liberty.

Gotta run. More later.

I have a feeling that if you were Black you also would have thought you were way behind

You've all been criticizing me for worrying too much about the size of my opponents' moyos. In this game (I had White), I focused on making territory while attacking, doing a very good job of getting a lot of territory on the left and top.

a very good job of getting a lot of territory on the left and top

W had some cash, but not a lot, not nearly enough --
correct in the hidden comments.

To over-estimate a moyo is not good; neither is to neglect it.
Difficult to find the balance and evaluate well at every move.

I hate fighting influence and moyo. I much prefer to break it up as soon as possible.

is a mistake according to josekipedia. I point it out, because the correct continuation involves an empty triangle, then a cut...empty triangle is good here!

would be a good time to invade before the moyo is solidified.

involves an empty triangle, then a cut...

Guzumi ; with a "push-and-cut" -- starting a fight.

Fedya wrote:

I have a feeling that if you were Black you also would have thought you were way behind

You've all been criticizing me for worrying too much about the size of my opponents' moyos.

Pas moi.

In this game (I had White), I focused on making territory while attacking, doing a very good job of getting a lot of territory on the left and top. . . .

So all the time I was making territory and not worrying about my opponent's moyo, my opponent was getting a big, impregnable moyo and more territory than me.

A couple of quick comments.

Not a bad place to jump to , attacking both above and below. The jump cuts a sector line, as Wilcox might say.

You point out that this jump attacks the Black stones on the top, but it also attacks the weak Black stones towards the bottom. That's good.

Not so good. Even if White cuts off and captures the Black wall, that's not very big, only a few stones. Better to continue to attack on a large scale, for instance with a two space jump to H-11, perhaps playing F-09 first.

Not having cut off the Black wall, but actually having strengthened it, White captures a single stone. Definitely not worth the trouble. F-09 looks good, now.

Black turns the table and attacks the attacker, topping the tree.

This is where the game was strategically lost. White had a good strategy of attacking top and bottom and pushing through into Black sphere of influence. Instead, White captured a couple of stones and made a little territory while allowing Black to save his groups and make strength in the center, solidifying a large framework. And to do so with sente and then enlarge his framework on the top right.