BQM49

  Difficulty: Advanced   Keywords: MiddleGame, Question

In the tradition of my constantly proposing immensely complicated middle game questions, I bring my latest problem... (By the way, I am Black) --BlueWyvern

[Diagram]
What to do, what to do?  

After a really steady careful fuseki, the board position is left like this. White closes the maneuverings on the upper side with 1. This is the point where I used to look at the board and go "D'uh, where the heck do I play?". After a bit of consideration, I made the 2 for 3 exchange on the lower side, then returned to the upper side. My question is, is this any good, and what sort of things should I be taking into consideration at this point in the game?

Addendum: A main point here, is I didn't have anything complicated in mind when I played 2, and it was very nearly an arbitrary decision that I thought would provoke a response because a follow-up cap at a might be useful, but I didn't really have any other mechanism for determining where to play next. All other strategy was thought out after White's response at 3.

Once again, I think I need a more thorough diagram to explain my question. /Game


[Diagram]
Return to the upper side...  

After planting a foothold on the lower side, I returned to the upper side and this is what happened.

Charles Matthews Here the 1/2 exchange is most regrettable for Black.

BlueWyvern The 1/2 exchange didn't feel bad to me because without it, it seems to me that White could have responded in a more aggressive fashion 3.

Charles Matthews It does very bad things to Black's right side. If White invades there successfully, Black is in trouble.


[Diagram]
Take the shape point  


Charles Matthews For consistency, Black should make a base on the lower side, starting at the key shape point 1. Simply playing the marked stone and leaving it isn't good style.

BlueWyvern: I thought maybe I should play some follow up, the only problem is, it seemed like abandoning the lone stone on top would be bad, and at the same time, if White is allowed to solidify the bottom he gets too much territory, so anything I did here, I figured I needed to keep sente, then move to the lone stone up top.

Charles Matthews Was all that based on an actual count? If Black gets the left side and the right side, and White gets the whole top side, is White ahead? I don't think so. Also Black has much more chance of expanding the right side into the centre, than White has of building anywhere. Simply creating a new weak group on the lower side isn't a satisfying way to play. (See greedy go, do not create two weak groups.)

BlueWyvern: My (possibly incorrect) analysis of this situation was that each of white's sides were slightly bigger than my own, and in my view, I wasn't exactly creating weak groups. For each of my lone stones in the top and the bottom, I wasn't so much worried about living/escaping with them so much as using the aji of living/escaping with them to keep white's sides in check. The stone on the bottom seemed shallow enough and light enough that containing it would take considerable effort on white's part, effort he probably would want to expend right away, but something he would have to constantly keep in mind. Incidently, later on in the white ended up having to cut off the top stone in gote allowing me to launch an assault on another part of the board with the thickness I got as a result of him cutting the stone off.

Charles Matthews I'm afraid this kind of thinking can lead to some bad exchanges. I think Black has achieved nothing so far on the lower side. White can attack in such as way as to reduce or invade the right side, which is Black's biggest framework, You really must be kind to your weak groups, and frameworks.

BlueWyvern But what exactly constitutes a weak group, as opposed to something mostly useful as a sacrifice? It sounds to me like it is assumed that I want to save both groups. I'm not hellbent on keeping both groups, in fact I'm not hellbent on keeping either group. Also, the aji, which I talk about below that ended up working, had it not worked, I wouldn't have gained anything on the lower side, but the presence of my stone would have caused me to gain big in the upper left, as had White taken the time to erase the potential, I would have had time to solidify the moyo I gained in the upper left to the point where only a very shallow reducing move would have worked.

I suppose the crux of my argument lies on the fact the top stone I intend to sacrifice with impunity, and the bottom stone I don't view as a weak group because it is pointing at a defect in White's position, namely, the keima he used to respond to it, although it is not a defect I can exploit straight away.

Charles Matthews What you are really saying is that the lower side stone is a kikashi. That's not what kikashi normally look like. White didn't answer submissively, but with a developing play.

BlueWyvern: I didn't intend for the lower side stone to be kikashi, and I didn't originally intend on abandoning it, but when White responded as he did, I saw what I thought to be an opportunity.

[Diagram]
White has a defect?  

When White played the marked stone, it at first appeared to be a developing play, but when I looked at it seemed to introduce a subtle defect in White's shape at a. If I were somehow able to develop thickness represented by the squares on empty spaces (not nessissarily at these points), the cut at a would threaten to lop off White's three stones in the corner; and were White to defend the corner, I would get a nice clean slice through the waist of his keima.

I originally left this position thinking that maybe I could devise some way to get thickness there later, not wanting to disturb the position as is, thinking it might result in aji-keshi. When I switched to the top and started to develop a wall along the top side, I suddenly noticed my opportunity. The moyo I was making would be so deep White would have to invade or reduce in order to stay in the game, at which point I could get the thickness I needed to exploit white's shape defect by attacking.

It turned out I did get the thickness later, the cutting aji was realized, and all my stones seemed to play some part even if it wasn't a direct obvious local result. The result was fairly smooth, the wall was built by sacrificing the weak upper stone, once the wall was in place, White had to invade, once white invaded, White had to defend, giving Black the needed thickness, and as settling stones generally happens in gote, Black was able to exploit the aji immediately after. Perhaps I read the situation wrong, but this is what I saw. Maybe I was looking too far into the position.

(black+circle) Just a note, the reason I view the single black stone at the top as easily is expendable is this. The situation was the result of this sequence in the corner:

[Diagram]
The corner sequence  

After the sequence from 1 to 3, I played the pincer at 4 as White did not yet have a stone in place at a. When White played 5 instead of taking the 3-3 point, I switched to taking more of the corner with 6 to 8. This seemed like a fair exchange to me, because White needs two more stones, a, and b before the lone black stone is in any serious trouble, and if Black choses to ignore both of these, White will have made two gote moves allowing Black to make up for the loss here with sente somewhere else.

Even after the second gote move, White would still need a third at c. to eliminate entirely the usefulness of Black's lone stone. From this point of view, my lone black stone on top doesn't appear to be a weak group at all, rather more like a kikashi stone that can be treated lightly and used some other time should the situation present itself, as its weakness has theoretically been compensated for by plays elsewhere on the board. --BlueWyvern


[Diagram]
Deep invasion  

Another important feature of the position is this invasion on the right. Starting at 1, White may be able to live here (this is a standard invasion point). Black would like to be able to play a in sente against the corner, threatening to cause trouble at b.


[Diagram]
Follow-up  



Locally Black can aim next at this typical ko lock tesuji.

Charles Matthews


[Diagram]
What to do, what to do?  

Dieter: I think forgetting about the order the moves were played in, may help to get a clearer view. Black has two important stones under attack: one at the top and one at the bottom. The question is which stone to continue with. The clues are (in my humble opinion): which stone has more room to become strong (and not heavy) and which stone is more damaging to the opponent's position? We can answer both questions the same way: the bottom stone. It is not a foothold yet and I think there lies the main flaw of your analysis.


[Diagram]
What to do, what to do?  

I thought perhaps it would be wise to write about how I followed up, so to give everyone a clearer picture of my thinking. Incidentally, I would like to point out that my move at the bottom was almost arbitrarily played, and any strategy I based on it was after having played it/seeing White's repsonse, which was part of the reason I posed this question in the first place.

I was trying to be a bit subtle in my approach, and perhaps I failed, but that is why I left my stone at the bottom. Right now it seems to me to be aimed at White's marked keima. It doesn't look like something now, but I thought perhaps I could make something of the keima cutting aji later. Also it seemed to me that my two "weak" stones were far enough apart that an effective double attack would be very difficult, and that more likely I could threaten to strengthen both at the same time with moves in the center forcing White to decide to kill one or the other. These two factor's in combination with the fact that attacking the stone at the bottom seemed two difficult to be profitable at this point led me to turn my attention back to the top.

So when I went up and put my lone stone on the top in motion, I was able to make a wall by pressing on White's marked stones at the top. I lost my marked stone, but I got a really deep moyo on the left side that White had to reduce while it still had only two big sides. Then I attacked White with my marked group in the lower left, essentially where I would have made a third wall for my moyo. I was able to build thickness, then all of a sudden when I played at a, White HAD to respond at b to keep me from swallowing the corner whole, then I got a nice clean perfect cut at c. Suddenly my "weak" marked stone that I had abandoned was in perfect position, because now White would have a difficult time getting help from his stones along the bottom and I was able to attack my opponents reducing moves with my stones at the bottom, and my framework on the right building a second moyo on the right.

I thought maybe this meant 1,2,3 in my first diagram were played well. Both of my "weak" stones seemed to end up being perfectly placed, but it seemed like perhaps it was just a fluke, as I only had part of this plan in mind when I left the bottom after considering the keima cutting aji, which is why I posted it. I had planned on trying to get some stones in the area that would make the cut a real threat, but I wasn't sure at how to do it at that time. Also I figure if I try to defend my move, I will learn more about what is wrong with it, then if I just smile and nod. :-) --BlueWyvern


Charles Matthews A player trying to save two weak groups, and develop two frameworks, all at the same time, is going to have full hands everywhere on the board. It's a 'busy' way to play. Strategic thinking is about prioritising, and making sure priorities don't conflict. Weak groups and framework strategies mix badly.


I understand that. The thing is, as I saw it, I wasn't doing all these things simultaneously. First, I didn't think the bottom stone was that weak, because in order to get rid of it as a threat, white would have to spend at least two moves. One to fix the cutting aji, and a second, maybe even a third to envelop the stone.

Next, when I built the first framework, I was really killing two birds with one stone. The building of the framework was required disposing of the usefulness of the stone on top. Once this was done I didn't have to think about building a framework, or saving the stone on top any more.

The creation of a second framework only came after white invaded my first one, and in attacking I was able to build a second framework AND utilize the potential of my second "weak" stone. So my feeling is that each moyo was linked to a weak stone and so a moyo and the realization of a weak stones potential were developed at the same time, and these tasks were sequential, I only had to worry about one at a time. Also in both cases the so called "weak" groups, which were really just one stone were absolutely key in building the resulting frameworks.

Lastly, I apologize for being stubborn, I am just trying to understand.

--BlueWyvern

Charles Matthews Maybe you fought well thereafter. I think you anyway started with the better position. But be aware that good plans rarely show inconsistency


I'm very interested in this game. Can you post the sgf of this game?


BQM49 last edited by 71.233.235.104 on January 28, 2012 - 19:28
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