( 984)

(Referenced by 297)

To enable the following sequence, we will take five pairs of / stones off the board.

:
Joachim's idea of first cutting at , to be able to play the more solid (with respect to Black's shape in the upper left corner) move at , does not effect the right side of the board.

Please note that cannot be played at here.

The / / stones will be played later. Black will still need one external ko-threat to win.

The remaining issue that has to be analysed is the question, whether Black has options, which will him allow to divert successfully from playing the protective move at in the upper left, which leaves White's upper string on the left sides with too many liberties, so that it is safe from potential Black ko-threats (in the case that the ko is started "late").

The result of our investigations is that there is no move for Black to get the desired result. Please note especially that - in the problem itself - has not been played at the moment that Joachim's solid move comes into play.