New Story Line 2022
KataGo's Bad-Shape Move in the Left Centre
VAR (.1)
Let's enter the world of amateurs ... | |
: ( 2039b) | |
White's last move created an additional approach-move liberty for her left-hand group, and so does not lose a tempo in the Main Semeai. Four Black moves are now needed for filling White's liberties in the left centre (3 x ; 1 x ), instead of only three before (3 x ; in principle). Additionally, Black must find a defense against White's cut at . | |
: Black will lose the ensuing ko-fight anyway, so he might consider simplifying the issue by immediately connecting at . : If she simply connected with , instead, Black would take the opportunity to capture White's single stone at the upper edge with , gaining two points at the cost of one Main Semeai Liberty, an effective advantage of one point. | |
: For further details of our analysis at the time, please refer to the history of our investigations ... As already mentioned above, we intensively investigated this line in a "no-kikashi" approach, i.e. without all of Black's kikashi , played, hoping that these could be utilised as Black ko-threats ... During the course of this investigation, KataGo found a surprising number of White ko-threats in Black's upper left corner, including and . On the other hand, Joachim discovered that Black's moves at and in the bamboo-joint ( had been exchanged for much earlier) were no valid ko-threats for him, as White was able to successfully ignore these ... | |
In order to profit from the ko-fight in the left centre, Black must connect the ko at . Black's last move did not lose a tempo in the Main Semeai. | |
: : | |
White's last move did not lose a Main Semeai Liberty. In principle, lost one tempo in the Main Semeai, but Black has to fill five points (3 x ; 2 x ) in the left centre now, instead of only four points before, so the net effect is zero. | |
: If he played elsewhere, instead, White would give atari at his two stones at the left edge with . After , would be another atari that Black could not connect with ; White would simply capture with . : : : : : Otherwise, Black would be able to utilise his liberty-occupying moves in the Main Semeai as ko-threats at an opportune moment. : | |
... | |
; : If he fully utilised his surplus Main Semeai Liberties for 4/4 reductions, the final scores of the Main Variations would become White + 1 / White + 3. Black will have to connect at and in the centre in the course of the ensuing Main Semeai. After White's decision point, Black will have to capture at , as White could give atari at his large group in the left centre. | |
Capture Variation: Compared to the superordinate variation, ...
In total, White gained one point. White + 1 => White + 2 | |
Semeai Variation: Compared to the superordinate variation, ...
In total, White gained one point. White + 1 => White + 2 | |