Variations of Our Solution (IIIa)
No Early Kikashi
This chapter explains all variations, as far as they do not relate specifically to the professional solution.
This is an extraction from the "Variations of Our Solution (III)" (513).
Order of Updates
At the beginning of the year, Dany introduced his atekomi to us, which leads to Dany's Ko. In the context of this ko, we began our investigations into what effect it would have if Black did without his kikashi beforehand, especially after Joachim's idea to tenuki at the very beginning (instead of playing KataGo's solid connection). Joachim discovered the value of White's kikashi in the lower left corner. | |
A few months later, Dany found that White's atari (played after her wedge in the left centre) should not be played so early, but kept in reserve as a ko threat. Dany also found that (especially in conjunction with an earlier White move in the hanezeki that pre-empts Black's kikashi there) White might be able to gain decisively by not connecting her two stones in the lower right. We called this "Dany's Sacrifice". | |
It was a big shock when I noticed that we had taken the order of moves of several exchanges (especially with "natural" looking moves) too easy, not considering their effect on the number of Black's Main Semeai Liberties at the moment of White's decision point (when she hs to choose between Capture, and Semeai, Variation). In this context, and in conjunction with Dany's atekomi, Joachim found that Black's atari at White's two stones in the lower left should be played very early. IF White connected (i.e. refuted Dany's Sacrifice), Black would gain two Main Semeai Liberties (what would remove some of his restrictions). | |
Joachim introduced his Final Ko in the Semeai Variation, but only as a side note. During my further investigations on this subject, it turned out that its application cases were far more numerous than Joachim had assumed.
Some special cirumstances given, Joachim's Final Ko will make it impossible for White to win the Semeai Variation if Black's large group has "only" nine Main Semeai Liberties (surely you will know already the Black's group survives the Semeai Variation with ten Main Semeai Liberties). | |
Joachim found another mistake in the order of moves, related to the number of Black's Main Semeai Liberties. If Black is par with the Punishment Semeai Liberty Level, he must not play his push at the top. White will continue with the Main Semeai thereafter, winning the Punishment Semeai. When working on the presentation of Dany's atekomi and the following Dany's Ko without White's atari in the left centre having been played beforehand, I realised that White's atari was not an additional ko threat. Black still has his atari at White's two stones in the lower right to be used as a ko threat, compensating for White's atari in the centre. |
Colours of the Boards' Edges
Darkgrey = 6 Main Semeai Liberties: | |
Darkred = 7 Main Semeai Liberties: | |
Brown = 8 Main Semeai Liberties: | |
Pink = 9 Main Semeai Liberties: | |
Lightgrey = 10 or more Main Semeai Liberties: | |
Lightbrown: | |
Darkbrown: | |
Cyan: |