Tesuji And Anti Suji Of Go / Errata

Page 35 diagrams 12 through 15

Various thoughts on the suji of connecting underneath

Dieter: I think that it is better for Black to immediately cut at 3 in diagram 13. If White captures, this reverts to diagrams 14 and 15. If White extends, Black connects. In the latter case, he has not made the exchange 1-2 in diagram 12 and thus not given away a stone for free.

Diagrams:

Connecting underneath

Problem: How to connect the three isolated black stones to the corner ?

Sakata's solution
Continuation

After , White can't connect at a because of shortage of liberties.

Variation in the book

So White will extend with and Black connects underneath.

Now for my suggestion:

Variation 1

Dieter: I think that it is better for Black to cut immediately with here.

Connecting underneath

If White captures, this reverts to Sakata's solution.

Variation 2

If White extends, Black connects. If we compare this result to the variation in the book, we see that in the latter Black makes the exchange of a for White b, a loss of two points compared to Black b - White a.

Page 38-39 diagrams 9 through 14

Problem diagram: Black to kill
Main variation

White is in shortage of liberties at a and b. Everything OK up until here.

Second variation

The second variation, presented as "if White makes the diagonal attachment of ", shows an extra stone . If is in place, at a still works. When it is not in place, too. This is just awkward but not really inconsistent.

Third variation

The third variation, White connecting at , requires a tesuji, namely , creating shortage of liberties. However, this is only necessary when is not in place. With in place, Black can play at immediately.

Third variation: a question mark

White can't play at a: she is already in shortage of liberties!

Third variation: cont.

The circled point is now empty. Now White can play at a.

So is better at a, making ko. --BillSpight

Third variation: cont.

Therefore, Black exchanges for and only then does he cut at . Now White is unable to play at a because of shortage of liberties.

Variation 2 being awkward, and the comments in variation 3 being inconsistent with the diagram, it is my opinion that should not be in place in diagrams 12, 13 and 14.