That move 24 was a favourite move of Lee Changho that fits well with his style: it stabilizes the white group and prevents black's good extension at a which develops from the shimari and aims at attacking the white wall. As the only unapproached corner was a 4-4 adding a move there is not so urgent compared to if it were a 3-4 (though making shimari from 4-4 is common these days).

One reason for the short extension is black doesn't like the following sequence in which white invades and immediately sacrifices in order to secure the corner against a 3-3 invasion (this was another of Lee's favourite tactics). White would then probably continue at a as in the game (black might resist and not defend at 7, or fight with 3).

Click Here To Show Diagram Code

[go]$$B
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X X O . . . . O . . . X . . . . |
$$ | . . X , O . O . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . O O . |
$$ | . . . O . X . 3 . 1 . . . a O O O X . |
$$ | . . . . O X 7 2 . . . . . X . X X X . |
$$ | . . . . 6 4 5 . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

So black plays the closer extension to avoid this sort of over-concentration. In fact Lee Sedol did the same thing in his 2nd game with AlphaGo, which then led to AlphaGo's famous shoulder hit from the 5th line to cause over-concentration from the other side!

I have been very delinquent in updating this, but I have a lot to update!

I'll update my goals and study effort soon, but first I've achieved the following:

1. I finally achieved my goal of breaking into the SDK world on IGS with a rank of 9k. Not sure how long I'll be able to keep it, but one step at a time.

2. I finally settled down to a rank of 7k on KGS. I'm not too far away from 6k, though. So, I'm aiming to get there in a month or so. I've been playing more on KGS lately than IGS because the style of play on KGS is new to me, and I'm trying to get used to it.

3. I haven't been able to play in-person games as frequently as I had hoped, but I've gone to a few local club meetings. I'm still trying to get used to the different perspective on has on the board when you play in person. Standing helps a bit, but it's still different!

4. I played in my first in-person go tournament a couple weekends ago. Based on my KGS and IGS ranking and the conversion chart on Sensei's Library, I entered my rank as 6k, and that seems to be about right. I lost my first game to a very bright 6k tween. He played very well. He probably would have beaten me regardless, but I helped him along. For some reason, I just couldn't settle down and focus. However, things fell into shape after that and I won my next three games. I was fairly happy with games two and three, but game four was a mess. I won, but I shouldn't have. I played a 4k opponent in an even game, and it seemed like the game came down to whether or not one of my groups could escape to safety. Eventually, my opponent resigned because he thought I had escaped. I thought the same, but afterwards, it became clear that we were both wrong. That said, it was a long day. So, not too surprising that we might make such a mistake.

I ended up at 5k once AGA crunched the numbers, but I'm guessing this is largely driven by my fourth game. So, I expect to settle down at 6k for now.

I played the following game on KGS today. I was ahead early on, but then made a series of mistakes to give the game away. This is a frequent cause of my losses, and I'm working to figure out how to correct it. In this game, I simply misread something at the very end, but that's happening less often. I think what I need to work on is to recognize when I'm ahead and then figure out how to simplify the game to avoid problems. I'm very bad at judging when I'm up in a game.

Anyway, my analysis is below. The only move about which I don't have a firm opinion is move 73:

Click Here To Show Diagram Code

[go]$$
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . O . . . . |
$$ | . . . X . . . . . X X X X O X O O O O |
$$ | . . O . . X . X X O O X O O X X X X . |
$$ | . . . O . . . X O O X O . O . X . . . |
$$ | . . . . . . X O . O X O O O . . . . . |
$$ | . . . O . . X O . O X X X X X . . . . |
$$ | . . . . . X O . O . . . . . . . . . . |
$$ | . . . . . X O . O X . . . . . . X . . |
$$ | . . . . . . . . . X . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . O . O . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . O , . O . . . X . O . |
$$ | . . B . . X . . . . . . . X . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

I expected the pincer after playing the approach (although I was expecting J3 rather then J4). I also considered jumping up and a double approach. My move gives white the start of a moyo, but with the stones in the bottom center on the fourth line, I feel like I have options to deal with it.

Here is the full game:

30 second 4k opinion: I like 73@C3, but I don't like 83@N5. You're not so strong on the bottom yourself and you don't have the correct local support to push and cut.

My blitz move for 83 is M2, giving yourself a bigger base and making White overconcentrated if he defends his territory on the left. (If he doesn't, you could end up reducing it to almost nothing, especially with ideas like F2.)

Thanks. I didn't realize that this group was that weak. And this is also consistent with the comment you made to my
last post. Looks like I generally need to be more careful about buttressing these weak groups, or at least recognizing when they are weak!

After allowing my opponent to live unconditionally -- yet again -- within the 4-4 small knight enclosure, I decided to do a deep dive on the invasion variations.

The following sgf provides the results:



I've included every variation that I've seen, but I'm sure that I'm still missing a few.

And in case anyone finds this useful, I also put together a series of sgf files that can be loaded into the Easy Go app to practice these sequences: https://lifein19x19.com/download/file.php?id=8524

References: The information that I have used to create this can be found in a wide range of sources, but I used Chikun's All About Life and Death (above) to double check my assessment of the status of some of the groups. I also have provided the relevant links for the standard groups (L, L+1, J+1) in the main SGF to Sensei's Library.

There seems to be a severe mistake in your line called "SGF 7". I added some comments there and on the line "sgf 1"

Thank you! Both for the correction and taking the time to even look. Let update the file in the original post to make the correction.

Despite clear mistakes, I feel like I played better than normal in this game. So, I thought I'd put it in my journal.

Hi BlindGroup,

This helps W fix his shape: W leans at Q12.
Probably the shared vital point is Q12.

Q12.

That's a good point. He played Q12 later but the position has changed by then. I didn't think of white playing it now. Black Q12 does look much stronger. Thanks!

Hi BlindGroup,

Maybe if you jump out and split W (I'm not sure what's best, e.g. o10),
W is busy.

R9.

e.g. M10 (re: ).

Not sure this is a wrong move.

How about L8 ?

The theme of the game:

You are on and off about large scale separation of groups. At several occasions you do make this your top priority: 29, 35, 47
At other occasions you don't: 25, 53, 61

A minor aspect is that local analyses and decisions are sometimes off: 37, 83, 123

At the upside, you win fights, like you say: the 77-79 combo and especially spotting the throw-in tactics at 147 !!! These are things that win games.

A minor thumbs up for your good peeps at 33, 129

Knotwilg, Thank you!

Your right that my local judgement is at times off -- still working on that.

Comment and question:

Move 23: I see your point. I considered extending, and I saw the white 24 response you note. But misjudged the value of it. So, this is particularly good feedback to get.

Move 33: I thought the marked move below was slow arguing that white should sacrifice and extend at A. But you have a different take "it would have been a big sacrifice, because Black gets all connected this way. And then what is the purpose of A if these stones don't cut anything?"

What is the value of whites stones as cutting black's shape? I suspect that I might be judging these positions incorrectly or not seeing an opportunity that these stones provide. I'm looking at this and seeing the black group in the right middle as being alive. And from that, it seems that the only thing white would lose in the sacrifice is the related territory, which if I'm estimating correctly is in the range of 10. That seems to small to care about right now. What am I missing?

Click Here To Show Diagram Code

[go]$$c
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O . X . . . . . X . . . . . . |
$$ | . . . , . . . . . X . . . . . X . . . |
$$ | . . O . . . . . . . . . . X . . X . . |
$$ | . . . . . . . . . . . . . O . O O . . |
$$ | . . . . . . . . . . . b . O . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . . O . . , . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . a . O . O X X . |
$$ | . . . . . . . . . . . . . . O . O O . |
$$ | . . . . . . . . . . . . . . . B . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . , . . . O . X . . . . . X . . . |
$$ | . . . . O . . . . . . . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Ed, Thanks! Very helpful!

Click Here To Show Diagram Code

[go]$$
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O . X . . . . . X . . . . . . |
$$ | . . . , . . . . . X . . . . . X . . . |
$$ | . . O . . . . . . . . . . X . . X . . |
$$ | . . . . . . . . . . . . . O . O O . . |
$$ | . . . . . . . . . . . b . O . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . . O . . , . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . 2 . O . O X X . |
$$ | . . . . . . . . . . . . . . O 3 O O . |
$$ | . . . . . . . . . . . . . . . 1 . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . , . . . O . X . . . . . X . . . |
$$ | . . . . O . . . . . . . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

If you don't respond to and let him connect, by cutting of the cutting stones at , then why play at all? What's the purpose of W2?

Click Here To Show Diagram Code

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

In this diagram, :w4 has a purpose of defending a group of stones that splits off black's middle from the corner. This is large scale separation, which needn't result in a kill but which puts a burden on black.

Click Here To Show Diagram Code

[go]$$
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . O . X . . . . . X . . . . . . |
$$ | . . . , . . . . . X . . . . . X . . . |
$$ | . . O . . 4 . . . . . . 2 X . . X . . |
$$ | . . . . . . . . . . . . . O . O O . . |
$$ | . . . . . . . . . . . b . O . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . . O . . , . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . O X X . |
$$ | . . . . . . . . . . . . . . O 3 O O . |
$$ | . . . . . . . . . . . . . . . 1 . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . , . . . O . X . . . . . X . . . |
$$ | . . . . O . . . . . . . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

If you think these White stones are wasted and you can allow Black to cut & connect with and , then you should play elsewhere, for example to strengthen the other group and then to take a large point.

I made a similar comment in this in a recent thread, and it's something I didn't really internalize until recently: there's a huge difference between 1) a group that you can prevent your opponent from killing, and 2) a group so strong that your opponent can't really even attempt to kill it (like your right side group if it connects).

If you have a type 1 group, your opponent will have tons of sente endgame moves and you'll likely end up with 2-4 points of territory. Meanwhile, he will have made strength that will help with his future endgame moves. And before you even get to the endgame, if he makes a dual-purpose move that happens to threaten your group, you'll have to defend against it, and he'll profit from his other purpose.

If you have a type 2 group, anything your opponent tries to do against it is "just points". You can ignore endgame moves if you have bigger moves elsewhere. You never have to worry about dual-purpose moves that threaten it. You can use it as a base that you can reach back to when you make invasions or endgame tesujis, knowing that it's safe.

Never seen or considered this distinction, but it makes a lot of sense. Thanks!

Ha, it turns out that my "similar comment in a recent thread" was about another one of your games. You liked that one too!

Ah, my poor memory! Thanks for the repeat. Hopefully, it sinks in this time!