Blighted Stones Have Little Use

A KGS Game  

The marked stones have been blighted. The upper stone more so than the lower.

I was thinking, to find this move, one could Ignore the Blighted Stones

Moves 112 on  

[10] And White cuts through ...

tderz ... which is big.
The corner is endangered.
To be cut through like this feels very bad.

Would there be a watari possible?

alternatives  

tderz: + are an often used tactique to give away the useless stones, but 4 stones will be cut off, which is still big.
Black cannot connect all by jumping to a.

alternative for  

tderz: could also test at a, which fails.
cannot connect herself and cut the black stones.

alternatives  

tderz: Black could end in sente (white will have exchanged Wa - Bb),
giving away at least 13 points. This could still be better than compromising the corner (in Gote) above ^[10].

Trying watari

watari?  

tderz: Can work?

watari?  

tderz: Because, there is a liberty at a, this does not work for White.

watari? resistance  

tderz: White could retract.

watari? resistance  

tderz: Cut could be answered like this.
White cannot proceed.
a and b are miai, both ending with an atari (c).

watari? Resistance, cut on the other side  

tderz: This is about similar to above.
Black stays connected.

Conclusion: Both are unimportant, however one could try to save some more endgame points by connecting the rest underneath.

watari?  

tderz: How to answer . If Black is careful, nothing special happens.

watari?  

tderz: [20] This is a safe way (but not the best),
Black could wait for giving atari a (it might not be answered if there is something bigger, than ca. 12 points?)

watari?  

tderz: [30] be careful: a possible exchange black b, white c (for gaining liberties)
endangers the black d group.
Which is a bit exaggerated nonsense, as Black only needs s for living.

watari?  

tderz: this costs nerves, but works after all.

watari?  

tderz: After the exchange a-b, White has the same problem as above,
fighting liberty e is only approachable after the moves c-d.

watari? resistance again  

tderz: Seeing all this, White could try resisting again like this, hoping for black a-b-c-d--white e.
If Black simply plays e, he should end up in the safe other variations.

watari? resistance again  

tderz: =x and with White has a connection problem.

watari? resistance again  

tderz: after black a-b-c one ends up in the variation ^[20] via transposition and with two more white stones captured.

Locally this feels (to me) as the fairest sequence for both, it depends much on how you can end in sente.

TA?: So the conclusion is that the blighted stones are useful in defending here? Does the title deserve a more fitting example?

Bill: Maybe the example deserves a better title. If the title suggests sacrificing weak stones, then that is good. But it should not suggest not making what use of them you can. (Their best use may lie in throwing them away.)

testing a group (1)  

tderz: Even more interesting is of course testing the whole big black -group with a white move =x (miai y, z, cf. [30]).

The idea is to cut off something of the black stones, when Black eventually has to defend somehow the cutting point s.

The idea behind it is that Black might be tempted to exchange t for u in order to block 's escape route and living by then by v instead of s.
This exchange t for u affects the semeai on the left.

It is not difficult to decide with which one to start.
Losing as mochikomi is a big loss. Better to start with in ^[10].

testing a group (2)  

tderz: More white stones are lost.

testing a group (2a)  

tderz: Exchanging - like this is better endgame for White (and white t remains as aji
hence Black cannot give atari u; cf. ^[30]).

is not necessary right now, hence could start at a after .

testing a group (3)  

tderz: Perhaps this is the point ...

testing a group (3a)  

tderz: If follows, to could follow
is not possible now, because
Black could play simply m or exchange t for u.

testing a group (3b)  

tderz: Having fun with a ko ?

testing a group (4)  

tderz: Black could better play , like this.