: ( 648ff)
White intends to play Dany's Ko.

: ( A 648fh)
White has to play this move anyway, if she wanted to win the ko in the left centre. Additionally, Black does not want to fight a ko, which is disadvantageous for him, therefore she can do so just now.

Black would win the game, if she insisted on fighting the ko in the left centre until the very end, instead, e.g. by capturing at , while refuting to prevent Black's kikashi at in the hanezeki.

However, by following Dany's suggestion of splitting the Nakade Sequence during this ko fight White would be able to increase her score in the alternative Main Variation.

:
Black connects the ko.

If he continued the ko fight, e.g. by capturing at , he would lose it, and White would win both Main Variations by one point.

:
White takes the last valuable point outside the Main Semeai area.

:
White plays her kikashi in the hanezeki to keep her additional point of territory there in the Semeai Variation.

:
White chooses Dany's Sacrifice in order to reduce Black's large amount of surplus Main Semeai Liberties.

Otherwise, she would be unable to capture Black's large group in the upper right in the Semeai Variation.

Black plays 0/2 reductions.

Capture Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black got an additional point of territory in the left centre.
• White did not capture Black's stone in the centre, so losing one point.
• Black does not need to capture White's two stones in the lower left, so gaining one point.
• Black captured White's two stones in the lower left, so gaining two points.
• Black got an additional point of territory in the hanezeki.
• White captured Black's stone in the lower right, so gaining two points.

In total, White lost four points.

White + 1 => Black + 3

Semeai Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black got an additional point of territory in the left centre.
• White did not capture Black's stone in the centre, so losing one point.
• Black does not need to capture White's two stones in the lower left, so gaining one point.
• Black captured one White stone less at the left, so losing two points.
• White captured an additional Black stone at the right, so gaining two points.
• White got an additional point of territory in the hanezeki.
• White captured one Black stone less in the lower right, so losing two points.

In total, White gained two points.

Black + 1 => White + 1