(Referenced by 826)

: ( 133)
Black tries to take advantage of his earlier move at (= ), which has weakened White's shape, by creating an additional cutting point. But Black's hopes to benefit from this just created weakness will be in vain.

We have adjusted the course of sub-variations here according to our latest insights into this position, so that the main line includes the "correct" sequence now.

: (A 142)
Now is the latest moment that Black should play Michael Redmond's kikashi in the bamboo joint, if he wanted to do so. Otherwise, Black will no longer be able to build a larger eye in the centre. He might have also played this move directly after the Hasami-Tsuke Sequence, with .

:
As far as the right side of the board is concerned, the circumstances are similar to the situation without Black's additional move of (= here). Black needs three gote moves, and one sente move, to occupy all White liberties from the left (, , , ). White has four outside liberties, but there is the cutting point of , which allows Black to take an internal liberty in sente. This means that there are three effective outside liberties for White, so has not won Black anything here.
However, the left side is different, because Black can create at least one "quick" ko-threat there. Here, White is unable play the sequence , , , , in following the main line of Joachim's idea of a new semeai ( 230), because Black's natural answer at unnecessarily takes White's group on the upper edge a decisive liberty.

:
So White plays two kikashi in the top left corner, beginning with this atari from the right, to enlarge the liberty count of her group on the upper edge. This seems to be the most straightforward procedure for White, who could also start the ko at successfully just now.

: (A 145)
Black answers White's push into the corner with the restrained move at , so White gained an additional liberty for her group on the upper edge. She has and now, instead of before.

In principle, this will enable her (but only in the case of an "early" ko-semeai that is shown hereafter) to successfully make a protective move on the left side later, depriving Black of most of his ko-threats there. This will help White to shorten the sequence.

Please note that White needs two moves - not only one - to erase all of Black's potential ko-threats in the nakade. Therefore, in the case of a "late" ko-semeai, White must not waste her just won liberty for a move on the left side of the board.

As with the main line of Joachim's Ko-Semeai, blocking directly from above with a move at , instead, does not work for Black. There are also further sub-variations on this topic ( 340).

:
White occupies a liberty of Black's nakade stones. This is the only protective move available on the left side that reduces the number of Black's ko-threats there to only two. No other White move will do the job ( 841). White must take into account that her -group has been reduced to only five liberties before.

(102 150)
White could also start the ko just now, but the ko-fight would unnecessarily drag on.

(A 152)
If White wants to start the ko "late", as with the main line of Joachim's Ko-Semeai ( 225), where has not been played, she has no time to play a protective move like this. On the contrary, such a measure would have an adverse effect.

:
Now, White starts the ko on the right side "early". The "early" ko is also shown in the theory chapter as FLAG 4b ( 1017).

Ko:

: (A 160)
Black will not benefit from using his ko-threats in the hanezeki, at (and at ).

(104 161; 109 162)
A move at , instead, will become even worse. White will be forced to answer at , occupying a shared liberty.

Black might do without the cut at , and continue with a ko-threat at . The result will not become worse for him.

:
Black's second, and last, valid ko-threat on the left side.

Ko: ; ; ;

: (A 163)
White could also use her gote-sente combination of , and , in the hanezeki, achieving a similar result.

:
Black has run out of valid ko-threats, so he has no other choice but to continue with occupying liberties. White's centre group has five effective liberties left, so it is no valid option for Black to connect the hanezeki's tail, instead, and re-capture the ko thereafter, because White will win the semeai with his connected group on the lower edge.

:
White simply connects the ko.

:
Black is unable to give atari at . White wins the semeai by one move.