EVENT
BOARDSIZE 19
SETUP W D16 K16 O17 Q5 R6 P8 D4 
SETUP B Q16 Q14 Q9 Q3 R4 R5 K4 
MARK 1@P8 A@Q6
COM
Problem 51. Black to play.  

White 1 is a light move. You might think that the cutting point
at A is a serious weakness in White's position, but Black must
not cut there. What should he do instead ? 
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B 1 P9
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Black 1 ...
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  VAR
  B 1 Q6
  COM
  Failure.

  It is tempting to cut at 1, but this falls into a trap.
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  W 2 P6
  COM
  White forces ...
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  B 3 Q7
  W 4 Q8
  B 5 R7
  W 6 R8
  COM
  ... with the sequence to 6 and Black's potential territory and
  moyo on the upper right suddenly disappears.
  <=
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  ENDVAR
W 2 O8
B 3 O9
COM
... and 3 are the most natural moves.
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W 4 N8
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After White 4, ...
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B 5 M10
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... Black jumps to 5 and a black moyo on the right side emerges.
Moreover, White's stones are still not settled.
<=
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