Variations of Our Solution (Ib)
KataGo's 2021 Solution
VAR (.3) (.3)
: ( 58bc) This early connection - which is not mandatory at all - is the game-deciding mistake. White must never ever connect her two stones, as long as the position in the upper left corner is still open. | |
: : Here, however, White cannot gain any local advantage by this exchange, but has enhanced Black's eye shape in the corner unnecessarwedeily. In addition, after White has already connected her two stones in the left centre (), White will never get a chance to connect her stone to the outside. : However, it can also be considered a kind of technical mistake, as it enhances Black's eye shape in the left centre unnecessarily (and is a genuine mistake, if played too early; 58dr). In general, it should be simply left unplayed. | |
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: : Alternatively, Black might consider descending to , as in the superordinate variation. The final scores of the game would not be affected. | |
: Alternatively, she could also push at . : However, this move can be considered a technical mistake, if played so early. White should simply do without. : : However, it might have been preferable to capture the other White stone with , instead, leaving absolutely no aji to the left. | |
: Alternatively, she might also consider connecting at , instead. Both points are miai. : By this move, Black gains two points locally, but loses only one tempo in the Main Semeai in return (please note that has become an approach-move liberty of his group). Therefore, the net effect of this capture is a gain of one point overall. : ( B 58bj) She would benefit by two points in the Semeai Variation, if she reduced Black's upper left corner before, starting with . : It would have been simpler to connect at immediately. : (C 58bk) Connecting his stone in atari, instead, would be a grave mistake. : Please note that the Central Semeai will not work for Black here, as his right-hand group has one outside liberty less than in the superordinate variation. | |
Black must not play any reduction. After her decision point, White will capture at in the centre; Black will push at at the upper edge. | |
Capture Variation: Compared to the super²ordinate variation, ...
In total, gains and losses compensate for each other. White + 1 => White + 1 | |
Semeai Variation: Compared to the super²ordinate variation, ...
In total, White gained two points. Black + 7 => Black + 5 | |