British Go Journal No. 64. March 1985. Page 26.
The original article used coordinates (such as K10) for most of this article. It has been altered to use marked up diagrams for the EBGJ.
Marks for various black moves.
Diagram X4 |
This replaces BGJ's Dia 5.
A more complicated position than the last, but the issues are better defined. I'll let one of the panelists describe what's happening.
Diagram X5 |
Roads: "The top right-hand and bottom left-hand corners are played out. Invading the top is not interesting because of the very strong white group to the right, and as for the top left corner, Black does not yet know if he wants to play F or G."
"So we look at the bottom right-hand corner and adjacent sides and notice a rather flat third-line position for Black developing along the lower edge and also two floating white groups - neither in immediate danger, but worth keeping separated."
All the other panelists agree that the lower side is the critical area, but are less unanimous about exactly where to play.
Diagram X6 Black O. |
Ansell: "A good start seems to be black O in Dia X5, shown in Dia X6. After black 5, which threatens L, if white jumps towards the left with either R, Black makes territory at the bottom and then plays H. An invasion of the top left corner or side is now threatened."
Apart from the suggestion of H, which should be at J or thereabouts, this answer sounds very plausible. However it meets with the disapproval of our strongest panelist, who proposes a tactical refutation.
Diagram 6 Black O refuted. |
Macfadyen: "If White can secure his three cutting stones in the lower left, he can invade the left side, and Black's ponnuki becomes almost worthless. For example if Black starts by attacking as in Dia 6, White will settle all his weak stones and after 14 the game is over."
There were other ideas for a splitting attack.
Rickard: "My choice is L, to prevent White's groups linking up by pressing black into a low position. However I have no great preference for L over other moves that do this."
Diagram X7 Black N, White Q. |
Smith: "One possibility is M. This is direct, but may be ambitious considering Black's positions on the lower side are a little thin. The quiet move at N seems more suitable, strengthening black and making it hard for white to link up. White may settle his group by playing Q as in Dia X7, but after this Black can take the initiative elsewhere (probably at the top)."
Finding the exact spot at the bottom certainly seems to have posed problems.
Macfadyen points out that White's stones are not as weak as one might think, because they can strengthen themselves by leaning on Black's left side group. He therefore prefers to play N, and keep his distance from this group.
The same conclusion was reached by Daly, although for not entirely the
"Black's stones around P are not yet safe. If white can cause confusion on the lower side he may be able to escape with his two weak groups. Black should play N, which is simple and safe. The best form of attack is defense."
But not every panelist wanted to keep white split.
Roads: "After the standard sequence following Q in the bottom right (see Smith's comments and Dia X7), White has the possibility of invading at H. Therefore the text-book move of K (1 in Dia 7) looks attractive for Black."
Diagram 7 Black K. |
"If White still plays the same sequence to strengthen himself, Black takes sente, since the invasion is no longer a threat. If White plays 2 in Dia 7, 3 and 4 follow, when Black is taking fourth line territory, and still has the possibility of splitting white."
Roads seems to be playing K to strengthen himself, thinking he can leave the splitting option for later. Another panelist chose K because he wanted White to connect.
Bates: "One's first instinct is the karami (splitting) attack at M, but this does not cover black's weakness around N. Also there is bad aji (potential) around his stone."
"Therefore one should instead consider driving White's groups together as in Dia 7. After 1-5 black has covered his weekness on the lower side and opened out his right side into the centre, while white has been driven along dame (neutral) points."
"Assuming a continuation like A-E, the position is developing into a firm lead for Black, while White still has the large weak group to consider (look at how much Black could gain from an attack at X)."
Bates doesn't seem to consider white running into the corner rather than out into the centre.
In my opinion, both N and K are reasonable moves. I have also given a consolation award to I, since it attacks and may make it easier for Black to invade the top.
When the position arose in my game with Andrew Daly during the 1984 Candidates tournament, I unfortunately did none of the good things suggested by our panelists, but instead played out at L. White went on to invade the lower side and eventually won by resignation.
The answer to problem 3 can be found on page 28.