: ( 648ab)
White plays in the hanezeki, pre-empting Black's kikashi at that point.

Please note that this move is gote in itself.

(A 648ap)
Black pushes at the top.

Black might consider pre-empting White's following kikashi in the hanezeki by giving atari at , instead. However, he will no longer win the Capture Variation, while not gaining overall (compared to the correct line of play below).

:
White immediately answers Black's forcing move locally.

She could play her kikashi in the hanezeki, instead, which is absolute sente.

We included this forcing exchange , at the very beginning of the following subvariations for if necessary.

: ( D 648ay; E 648bn; F 648br)
Black plays KataGo's solid connection.

However, Black has to play at , instead, closing the hole in the left centre, and simultaneously occupying a liberty of White's group at the left.
This subvariation is the second one, where Joachim found a Final Ko in the Semeai Variation, which benefits Black.

Compared to the correct line of play below, Black would lose one point in the Capture Variation, if he played the atari at in the lower left "early", instead.
Capturing White's single stone at the upper edge with "early" will result in the same final scores as here (correct line of play below assumed).

: ( A , B 648cc;  C 648cd)
White's push from above is a grave mistake here, robbing White one Main Semeai Liberty.

White were better if she connected her single stone at the upper edge immediately (i.e. after inserting her kikashi in the hanezeki), instead.
However, White's best option here is to continue with the Main Semeai, instead, and to utilise fully that Black's actions are largely restricted by already being par with the Punishment Semeai Liberty Level.

:
White connects her single stone at the upper edge, but which loses another Main Semeai Liberty.

:
Black continues with the Main Semeai by giving atari in the lower left.

: ( A 648cj)
White connects.

Black has sufficient Main Semeai Liberties to spend, so White will not choose Dany's Sacrifice.

However, with the knowledge about Joachim's Final Ko in the Semeai Variation, White will now choose Dany's Sacrifice. This will reduce Black's Main Semeai Liberties by two, and so inhibit the application of Joachim's finding.

White will play her kikashi in the hanezeki, instead.

: ( A 648ck)
By playing this atari in the hanezeki, Black gains one point overall, despite this move is gote.

However, with the knowledge about Joachim's Final Ko in the Semeai Variation, Black will not play this move, but continue with the Main Semeai, instead.

White did not want to pre-empt Black's atari by playing her own kikashi , . Unnecessarily, White would lose one point in the Capture Variation, while still being unable to capture Black's large group in the upper right in the Semeai Variation.

:
The Main Semeai continues.

Black plays 2/3 reductions.

Capture Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black did not capture one White sente in the left centre.
• Black's cumulated gain in the lower right corner is two points.
• White did not capture one Black stone in the lower right, so losing two points.

In total, White lost one point.

White + 2 => White + 1

Semeai Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black did not capture one White sente in the left centre.
• Black's cumulated gain in the lower right corner is two points.
• White captured an additional two Black stones in the lower right, so gaining four points.
• Black did not capture one White stone in the lower left corner, but an additional one in the left centre, so the net effect is zero.

In total, White gained five points.

Black + 4 => White + 1