Let's learn flawless fighting!

TelegraphGo · Post by **TelegraphGo** » Thu Sep 17, 2020 5:51 am

Almost all of my students have eventually asked me, "What am I supposed to read during my game?"

It's one of the hardest questions for me. I can give a few general principles, some examples of what sequences I would read at various points in their game, but often I wish I could give a more encompassing answer.

I'm starting this thread as an attempt to compile such an answer. I'm going to post some middlegame fighting scenarios I come across and try to focus on not only the answer but the thought process.

I'm trying to cherry pick for clarity. All the problems will share a few characteristics:

1) KataGo suggests that there is only one best move and every other move is at least 1 point worse.
2) I'm capable of finding a clear and concise thought process to conclude that the best move is indeed correct.
3) There are vital sequences that need to be read to reason about the problem.
4) There's some kind of motif to take away at the end of the day.

I would be thrilled if anyone else shares similar middlegame problems.

Anyway, here's the first problem. It comes from a 7d game I played on Fox, in which I (black) traded the bottom side to encroach upon my opponent's base in the upper right. How should I continue? What should I read to become completely confident that the move I'm choosing is best?

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O O O O . O . X . . . . . . . | $$ | . . O O X X X O X . . . . . . . X . . | $$ | . . O X . . . X . X . . X . . X . O . | $$ | . . O X . O . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . O . . | $$ | . . . . . X . . . . . . . . O . . . . | $$ | . . . . . . X . . . . . . . . . O X . | $$ | . . X O . O X . . . . . . . . . W X . | $$ | . . X , . . O . . , . . . . . X . O . | $$ | . . . O O X O . O . . . . . . . X O . | $$ | . X . . X O X . O X O X . . . . X X . | $$ | . . . . O O X . O O . O X . . . . O . | $$ | . . . O . . X . O . O O X . . . X . . | $$ | . . O . . . . . O O X X . . . . . . . | $$ | . O . O . . X . . , . . . . . X . . . | $$ | . . O X X . . X O O X O . X . . . . . | $$ | . X X . . . X O O . O X O O . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Hint:

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O O O O . O . X . . . . . . . | $$ | . . O O X X X O X . . . . . . . X . . | $$ | . . O X . . . X . X . . X . . X . O . | $$ | . . O X . O . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . . O . . | $$ | . . . . . X . . . . . . . . O . . a . | $$ | . . . . . . X . . . . . . . . . O X . | $$ | . . X O . O X . . . . . . . . . W X . | $$ | . . X , . . O . . , . . . . . X b O . | $$ | . . . O O X O . O . . . . . . . X O . | $$ | . X . . X O X . O X O X . . . . X X . | $$ | . . . . O O X . O O . O X . . . . O . | $$ | . . . O . . X . O . O O X . . . X . . | $$ | . . O . . . . . O O X X . . . . . . . | $$ | . O . O . . X . . , . . . . . X . . . | $$ | . . O X X . . X O O X O . X . . . . . | $$ | . X X . . . X O O . O X O O . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Can I play the pushing move at "a", or should I capture at "b"? How can I be completely confident in my decision?

Answer is coming in a day or two.

Knotwilg · Post by **Knotwilg** » Thu Sep 17, 2020 6:24 am

What I read is:

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O O O O . O . X . . . . . . . | $$ | . . O O X X X O X . . . . . . . X 9 . | $$ | . . O X . . . X . X . . X . . X 8 O . | $$ | . . O X . O . . . . . . . . d b 6 7 0 | $$ | . . X X . . . . . . . . . . c a O 5 . | $$ | . . . . . X . . . . . . . . O 4 3 1 . | $$ | . . . . . . X . . . . . . . g e O X . | $$ | . . X O . O X . . . . . . . . f O X . | $$ | . . X , . . O . . , . . . . . X 2 O . | $$ | . . . O O X O . O . . . . . . . X O . | $$ | . X . . X O X . O X O X . . . . X X . | $$ | . . . . O O X . O O . O X . . . . O . | $$ | . . . O . . X . O . O O X . . . X . . | $$ | . . O . . . . . O O X X . . . . . . . | $$ | . O . O . . X . . , . . . . . X . . . | $$ | . . O X X . . X O O X O . X . . . . . | $$ | . X X . . . X O O . O X O O . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

This is the main line I read. I can see Black's success but I can't read out all possible implications. In a real game I would therefore choose the safe option. I am 2d on KGS, 4d on fox, 1d on OGS.

Edit: and then when visualizing the 17 moves I've read, I see that I've probably misread the continuation.

jlt · Post by **jlt** » Thu Sep 17, 2020 6:56 am

I (1k on Fox) read more or less the same as Knotwilg (with

and

interchanged) but things get too fuzzy by move

or so.

Bill Spight · Post by **Bill Spight** » Thu Sep 17, 2020 7:29 am

TelegraphGo wrote:1) KataGo suggests that there is only one best move and every other move is at least 1 point worse.

I take it you mean 1 board point, not 1 percentage point.

gennan · Post by **gennan** » Thu Sep 17, 2020 12:16 pm

For human players (with limited abilities compared to AI), there are other things to consider when faced with a choice like this in a real game, such as:

- How confident are you about reading deeply and accurately?
- How good is your positional judgement?
- How do you feel about your endgame ability?
- How much time do you have left?

Before diving into such a reading challenge in a real game, you may consider these things and ask yourself if you really need to play the sharpest and most risky variation. If you're clearly leading the game with a more cautious, simple variation, then that's probably your wisest choice.

Shaddy · Post by **Shaddy** » Thu Sep 17, 2020 1:15 pm

gennan wrote:For human players (with limited abilities compared to AI), there are other things to consider when faced with a choice like this in a real game, such as:

- How confident are you about reading deeply and accurately?
- How good is your positional judgement?
- How do you feel about your endgame ability?
- How much time do you have left?

Before diving into such a reading challenge in a real game, you may consider these things and ask yourself if you really need to play the sharpest and most risky variation. If you're clearly leading the game with a more cautious, simple variation, then that's probably your wisest choice.

IMO, you should trust your own reading. Give yourself the chance to blow it and lose because you missed a variation. It's valuable feedback for improvement.

Shaddy · Post by **Shaddy** » Thu Sep 17, 2020 1:16 pm

Knotwilg · Post by **Knotwilg** » Thu Sep 17, 2020 4:40 pm

I had "seen" shaddy's 5 but I had missed his 11.

Post by **Joaz Banbeck** » Thu Sep 17, 2020 9:26 pm

I trust Shaddy's reading too.

TelegraphGo · Post by **TelegraphGo** » Fri Sep 18, 2020 3:17 am

Bill Spight wrote:
TelegraphGo wrote:1) KataGo suggests that there is only one best move and every other move is at least 1 point worse.
I take it you mean 1 board point, not 1 percentage point.

Yes, 1 "real" point.

gennan wrote:For human players (with limited abilities compared to AI), there are other things to consider when faced with a choice like this in a real game, such as:

- How confident are you about reading deeply and accurately?
- How good is your positional judgement?
- How do you feel about your endgame ability?
- How much time do you have left?

Before diving into such a reading challenge in a real game, you may consider these things and ask yourself if you really need to play the sharpest and most risky variation. If you're clearly leading the game with a more cautious, simple variation, then that's probably your wisest choice.

These human psychological concerns are exactly why I chose to start with a problem where backing off would leave me slightly behind, but going for it (with good reading) would leave me comfortably ahead.

I hope that this thread will be a place where we can briefly step away from asking these excellent questions that help us win games at our level more often. Instead my goal is to ambitiously study "flawless fighting", the moves that can win games that are way above our level.

I like the way Shaddy put it - give yourself a chance to blow it as valuable feedback for improvement. These problems are not going to be as murky as most real game scenarios anyway, I hope.

On to the answer to problem #1! Shaddy got it correct, so congratulations to him!

My point behind this problem was to expose a bit behind the proverb, "Always read the most violent move first." Personally, I 'read' two moves deep into black's "b" backing off variation before reading the more violent pushing move at "a". I think that's totally fine in terms of thought process - it's way easier to read, so we can quickly establish a baseline move to compare our results against.

We all agree it's easier to read, but regardless I'd like to pose the toddler's question of "why?" Why do we all know that variation will settle faster, and read it first? My opinion is that it all has to do with how much use we make out of cutting points. The faster you take a cutting point, the faster you convert difficult aji into calculable tactics. So I believe that in this sort of fighting situation we can retranscribe the proverb as "Always read the move that makes use of cutting point aji first, first."

Essentially, once you take a cutting point there's almost always going to be some relatively forcing lines, and within 1-10 moves of accurate reading you should be able to draw a conclusion as to the merit of your cutting timing. So instead of first reading the lines where the cutting point conclusion will come later, first read the lines where you can gain useful decision-making information as soon as possible.

I meant to pose this problem as a threefold attack at that idea- first, the initial position. Secondly, move 5, where there were several promising options, each with somewhat unclear payoff.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O O O O . O . X . . . . . . . | $$ | . . O O X X X O X . . . . . . . X . . | $$ | . . O X . . . X . X . . X . . X . O . | $$ | . . O X . O . . . . . . . . . . b . . | $$ | . . X X . . . . . . . . . . . a O c . | $$ | . . . . . X . . . . . . . . O 4 3 1 . | $$ | . . . . . . X . . . . . . . . . O X . | $$ | . . X O . O X . . . . . . . . . W X . | $$ | . . X , . . O . . , . . . . . X 2 O . | $$ | . . . O O X O . O . . . . . . . X O . | $$ | . X . . X O X . O X O X . . . . X X . | $$ | . . . . O O X . O O . O X . . . . O . | $$ | . . . O . . X . O . O O X . . . X . . | $$ | . . O . . . . . O O X X . . . . . . . | $$ | . O . O . . X . . , . . . . . X . . . | $$ | . . O X X . . X O O X O . X . . . . . | $$ | . X X . . . X O O . O X O O . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Personally, I read "a" first, and then immediately stopped reading when white replied "c".

Then, between "b" and "c", I read "b" first. It's not necessarily because it's the more violent move, both moves are pretty violent. It's because "b" uses the cutting aji at "a" more directly than "c". I think the reading is then relatively simple, until we get to move 11, where Shaddy showed us the peeping tesuji.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O O O O . O . X . . . . . . . | $$ | . . O O X X X O X . . . . . . . X . . | $$ | . . O X . . . X . X . . X . . X . O a | $$ | . . O X . O . . . . . . . . . . X X O | $$ | . . X X . . . . . . . . . . . X O O O | $$ | . . . . . X . . . . . . . . O O X X . | $$ | . . . . . . X . . . . . . . . . O X . | $$ | . . X O . O X . . . . . . . . . O X . | $$ | . . X , . . O . . , . . . . . X O O . | $$ | . . . O O X O . O . . . . . . . X O . | $$ | . X . . X O X . O X O X . . . . X X . | $$ | . . . . O O X . O O . O X . . . . O . | $$ | . . . O . . X . O . O O X . . . X . . | $$ | . . O . . . . . O O X X . . . . . . . | $$ | . O . O . . X . . , . . . . . X . . . | $$ | . . O X X . . X O O X O . X . . . . . | $$ | . X X . . . X O O . O X O O . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Even here, it looks like black should be losing this liberty race. The only way to save the group is, drumroll please, taking advantage of the white's cutting aji at "a" as soon as possible. It can be hard to even notice that there is such cutting aji!

Wasn't that a neat problem? I don't have any more that are quite this good, so I'll say again that I'd be absolutely thrilled if anybody else posts a problem or two of their own, as long as they follow the 4 guidelines in my first post.

Problem #2: A much easier one!

This one comes from a no-komi game I (black) played against an 8dan on Fox. After some very embarrassing mistakes on the top of the board, I found myself behind, and I launched what could have been a brilliant attack on his bottom side group. Alas, I failed at the critical juncture.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X . X . . . X . . . . . | $$ | . . . . O . . O X O O . . . . O . . . | $$ | . . X . . O . O X W . O X . X O . . . | $$ | . O . . . . . X O O O . X . X . . . . | $$ | . . O . . O . X X X . O . . . . . O . | $$ | . . . O O X X . O X O . O . X , O . . | $$ | . . . . . O . X X . X O . O . X X O . | $$ | . . . . . . O X . . X . O . X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Since I'm sure you're all going to get this one, I'd like to ask what your strategies/habits are to help you avoid falling into this trap that I fell into? Clearly my habits need changing, since I failed this one in my game despite talking about the idea with my students many times

jlt · Post by **jlt** » Fri Sep 18, 2020 6:12 am

I'll try something but it's not easy for me.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X c X . . . X . . . . . | $$ | . . . . O . . O X O O d . . . O . . . | $$ | . . X . . O . O X W e O X . X O . . . | $$ | . O . . . . . X O O O a X . X . . . . | $$ | . . O . . O . X X X b O k l . . . O . | $$ | . . . O O X X . O X O i O f X , O . . | $$ | . . . . . O . X X . X O j O . X X O . | $$ | . . . . . . O X . . X h O g X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

"a" is sente because it threatens "b" (if Black could play at both places, then White would be disconnected and the bottom group is dead since "i" is not an eye).

So let's try

at "a" and

at "b". Then

at "c" is necessary, otherwise White will connect to a living group.

Now, "e" is not an eye yet. If White plays at "d" to make an eye, then Black has no choice but to plays at "k", otherwise "i" becomes an eye. But then White plays at "f", so "g" and "h" are miai and "j" is an eye.

So

at "a" doesn't work. Let's try

at "b",

at "a" and

at "c". It seems that Black can kill by ko.

Knotwilg · Post by **Knotwilg** » Fri Sep 18, 2020 6:52 am

It took me some time to get to the root of the problem but I think I have it now.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X 1 X . . . X . . . . . | $$ | . . . . O . . O X O O . . . . O . . . | $$ | . . X . . O . O X W . O X . X O . . . | $$ | . O . . . . . X O O O . X . X . . . . | $$ | . . O . . O . X X X 4 O . . . . . O . | $$ | . . . O O X X . O X O . O C X 3 O . . | $$ | . . . . . O . X X . X O . O . X X O . | $$ | . . . . . . O X . . X C O 2 X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

If

then

can be played in sente and then

fixes all eye shape problems. White has a second eye because of the circled miai.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X 1 X . . . X . . . . . | $$ | . . . . O . . O X O O . . . . O . . . | $$ | . . X . . O . O X W . O X . X O . . . | $$ | . O . . . . . X O O O 4 X . X . . . . | $$ | . . O . . O . X X X 3 O 6 . . . . O . | $$ | . . . O O X X . O X O 5 O . X 7 O . . | $$ | . . . . . O . X X . X O . O . X X O . | $$ | . . . . . . O X . . X . O 2 X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Black can ignore

to force a connection at

then another one at

before defending at

It's a ko.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X 1 X . . . X . . . . . | $$ | . . . . O . . O X O O . . . . O . . . | $$ | . . X . . O . O X W . O X . X O . . . | $$ | . O . . . . . X O O O . X . X . . . . | $$ | . . O . . O . X X X 2 O C . . . . O . | $$ | . . . O O X X . O X O . O . X 5 O . . | $$ | . . . . . O . X X . X O . O . X X O . | $$ | . . . . . . O X . . X . O C X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

However,

can play here directly to make the circled miai.

Click Here To Show Diagram Code: [go]$$c Black to play. $$ --------------------------------------- $$ | . O O O X . . . . . . . . . O . O . O | $$ | . O X X . . . . . . X X O O O O X O . | $$ | . O X . X X . . . . X O . X O X X O X | $$ | . O O X . . X . . X . O X X O X . X O | $$ | . O X X . . . . . . . . X O X X O X . | $$ | . O O . . X O . . X . O . O . X X . . | $$ | . X O . O O O . . . . . . . O O X X . | $$ | . X O . . . . . . O . . . . . . X O . | $$ | . . X . . . . . . X X X . X O O O O . | $$ | . . X , X X . . X , O . . . . , . . . | $$ | . . . X O . X X . X . . . X . . . . . | $$ | . . . . O . . O X O O . . . . O . . . | $$ | . . X . . O . O X W . O X . X O . . . | $$ | . O . . . . . X O O O . X . X . . . . | $$ | . . O . . O . X X X 1 O . . . . . O . | $$ | . . . O O X X . O X O . O . X , O . . | $$ | . . . . . O . X X . X O . O . X X O . | $$ | . . . . . . O X . . X . O . X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

So in order to get the ko I think Black needs to play

first.

If I would find this in a real game, it would be a matter of luck, in the sense that I can read this but I don't have strategies to avoid missing the line.

When reading this out, of course there's the idea of the "vital point shifting up".

Life In 19x19

Let's learn flawless fighting!

Let's learn flawless fighting!

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Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!

Re: Let's learn flawless fighting!