: ( 648bo)
Black continues with the Main Semeai, occupying one of White's liberties.

:
White is bound to the Main Semeai.

: (136 648bq)
Black plays KataGo's solid connection.

Alternatively, he could play also atari at the upper edge.

:
White blocks at the upper edge.

:
Black connects.

Black plays 0/1 reduction.

Capture Variation:

Compared to the superordinate variation ...

• White got an additional point of territory at the top.
• Black did not capture one White stone in the left centre, so losing one point.
• White did not get any territory in the left centre, so losing two points.

In total, gains and losses compensate for each other.

Black + 3 => Black + 3

Semeai Variation:

Compared to the superordinate variation ...

• White got an additional point of territory at the top.
• Black did not capture one White stone in the left centre, so losing one point.
• White did not get any territory in the left centre, so losing two points.

In total, gains and losses compensate for each other.

White + 3 => White + 3