4d Tygem game

[marvin]

Hi

It is a bit quiet in this subforum, I guess everybody is just asking AI.
In case you wish to go over my game, I would be interested in the moves which you see as mistakes and why.
Thanks

[Shenoute]

I'm 6d on Tygem, so my comments are for what they're worth

if b isn't going to cut, pushing here seems to weaken the two stones
and , looks like b has only helped w in this area
this looks like it just helps w turning the top into territory
I don't understand this move. Was the goal to capture the white stone at F16? But the b group is already alive so capturing is really small
playing from the group that is already alive instead of using sente to reinforce the cutting stone. Forcing w to answer in this area will only weaken the cutting stone and 91 is a dame. Why not play at 93 immediately?
there is still a lot of aji at the top and this seems to help w tremendously (and the resulting b group is not overly safe...)
101 seems to me w his looking for ways to place stones facing the center in order to harass the b group. In this kind of situation, I like playing a nobi towards the center (F10). It puts pressure on the w stone and helps the center group too. Hane below generally helps w placing stones towards the center
107 the center doesn't feel completely safe to me, even after this move, and letting white play 108 means three weakish groups for b (R10, R17 and the center one). I think I'd have connected underneath and hoped for the best in the center
109 feels like it helps white getting rid of the b stone's aji without really helping the group on the side

[marvin]

Thanks, these are all excellent points.

For 87, the idea was to reduce the centre or side. I expected K15 and I reduce the centre and get some points, while w gets M16 area. What would you play instead?

[Shenoute]

Thanks, these are all excellent points.

For 87, the idea was to reduce the centre or side. I expected K15 and I reduce the centre and get some points, while w gets M16 area. What would you play instead?

But 87 pushes w from behind and helps him build the side and center. If the goal is to reduce the center, why do it after w has gotten stronger in the area (same as the 91-92 exchange)?
If black really got something with the 83-87 sequence maybe it would be a normal exchange but I don't see these moves building anything interesting for b.

I marked the exchanges I find uninteresting. To me, all the w stones appears to be doing something (facing outward, making the the top and center stronger) while the corresponding b stones are either dame or, at most, making a couple points (around F19). And all these exchanges were initiated by b.
Or, to put it otherwise, at w only had some potential at the top and the Q4 stones may have become a target. Only 13 moves later, after , the Q4 stones are solid and make a nice wall towards the center (important if black wants to reduce the center/top and a fight develops), and the top is much closer to becoming white's than before. I'd say that w's position has been significantly improved just by him answering b, all without b gaining much.
I'm not saying this is game over for b or anything! just that w's life has been made easier.


As to what I'd play at 87, Q14 looks interesting. It reinforces b in the area, probably making some points, may help in reducing the center, prevents w from playing around here in sente and building the center. But maybe I'm only interested in it because of what happened later in the game

[Uberdude]

Shenoute covered some of the bigger mistakes in later fighting, but to me the first mistake is 17. With r14 low this extension looks very low and unappealing. When you see bots play it as an attack against the wall if is usually much more spacious e.g. just a black stone at q16. q14 is a better point, indeed I want to play there for a long time throughout the game.

[Knotwilg]

The move that struck me most as counterproductive was 83. Probably White is already well in the lead at that point, as Black's territory doesn't really outperform White's plus komi, and White has more scope for central or top side development. Black's biggest side is the right side and it needs reinforcemet. So I would have stretched up at Q14 even if that elicits White to develop the center.

I concur with many of Shenoute's other comments too.

[marvin]

Thanks for the additional replays.
Seeing it like that, it seems quite obvious that the marked exchanged are bad.
But I still don't really get it how 83-89 is that bad for me, apart from seeing that Q14 (and that part of the board) is more urgent.


Q14 is an interesting move, that I intuitively wanted to play. But I could not understand concretely why it is large enough. I saw that it is reverse sente, but I missed that w gets much more than just Q14, and it influences Q16 group. I will play around this shape a bit more, maybe I will post an update about it.

@Knotwilg: "Probably White is already well in the lead at that point" Interestingly, I felt quite good at this point, with the game being slightly good for me, and looking forward to playing good endgame.

[marvin]

Thanks again for the replies, they were really helpful. I composed sgf as a reference.
I also tried to evaluate the position at move 82, but I realised I don't really know how to evaluate influence well enough for it to be helpful. Knotwilg, how differently would you count secured(as Antti suggests) territories? Or do you also count potential ones?
Anyhow, I can't do it during the game in 30s.

[Knotwilg]

Sometimes you expect Kata to draw the territory card and it plays the one of influence, then again it's the other way around

Can't argue with Kata-san but here's how I thought White could gain the upper hand fast.

$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . 3 . . . . . . . . . . . |
$$ | . . X X . . . 1 2 . . . . . O X X . . |
$$ | . . O X . O . . O , . . . O . O X . . |
$$ | . . O X . . . . . . . . . . . O 7 . . |
$$ | . . O X . 8 . . . . . . . . . 6 X . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . . . . . . 4 . 5 . . |
$$ | . . O O . O . . . . . . . . . . . . . |
$$ | . O X , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . X . . . . . . . . . . . . X . . |
$$ | X . X . X . . . . . . . . . . . . . . |
$$ | . X . X O O . . O . . . . . . . . . . |
$$ | . O X . O X . X . . . O O O . . . . . |
$$ | . . O O O X . . . , . X O X O O O . . |
$$ | . O X X X O O O O . O . X X . X X . . |
$$ | O X . . . X X X . . . . . X . . . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . 3 . . . . . . . . . . . |
$$ | . . X X . . . 1 2 . . . . . O X X . . |
$$ | . . O X . O . . O , . . . O . O X . . |
$$ | . . O X . . . . . . . . . . . O 7 . . |
$$ | . . O X . 8 . . . . . . . . . 6 X . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . . . . . . 4 . 5 . . |
$$ | . . O O . O . . . . . . . . . . . . . |
$$ | . O X , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . X . . . . . . . . . . . . X . . |
$$ | X . X . X . . . . . . . . . . . . . . |
$$ | . X . X O O . . O . . . . . . . . . . |
$$ | . O X . O X . X . . . O O O . . . . . |
$$ | . . O O O X . . . , . X O X O O O . . |
$$ | . O X X X O O O O . O . X X . X X . . |
$$ | O X . . . X X X . . . . . X . . . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]