The book shows how
here fails:and how
here fails:But it does not show what happens after this
:Is this loose ladder really the best black can do?
Knight-move tesuji
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PeterPeter
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Knight-move tesuji
I am reading about the knight-move tesuji at 'b' to capture a white group like this, where 'a' fails after repeated ataris by white.
The book shows how here fails:
and how here fails:
But it does not show what happens after this:
Is this loose ladder really the best black can do?
The book shows how
here fails:and how
here fails:But it does not show what happens after this
:Is this loose ladder really the best black can do?
Regards,
Peter
Peter
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Uberdude
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Re: Knight-move tesuji
Are you sure that's what the book says? As you say white can escape so black fails.
This is the knight's move that works in this situation (sometimes both work, but here the shortage of liberties of the black stone at the top means black has to go this way).
If you move one white stone then b works ...
This is the knight's move that works in this situation (sometimes both work, but here the shortage of liberties of the black stone at the top means black has to go this way).
If you move one white stone then b works ...
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PeterPeter
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Re: Knight-move tesuji
Yes, sorry, I had the arrangement of white stones slightly wrong, and did not appreciate how much of a difference that would make to black's weak stone and the sequence.
Regards,
Peter
Peter
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lightvector
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Re: Knight-move tesuji
There is a useful heuristic in Go where if a move creates a connection that's too weak, then often if you "pull the move back" a space, usually creating a knight's move, you get a connection that works.
For example, in the following position, ''a'' does not work for black because white can push and cut at ''b'' and capture either the corner or the outside. But if black pulls his stone a step further away from white and plays the knight's move at ''c'' instead, then he produces a safe connection.
Similarly in this classic tesuji, ''a'' doesn't work for black, but ''b'' does.
In your example, looking at the two marked black stones, the one on the top side is weaker. So applying the heuristic, your first instinct should be ''a'', pulling the netting move back into a knight's move on the weak side. As opposed to ''b'', which makes the gap on the weak side even larger (two spaces instead of one space) and therefore even easier to for white to break through.
For example, in the following position, ''a'' does not work for black because white can push and cut at ''b'' and capture either the corner or the outside. But if black pulls his stone a step further away from white and plays the knight's move at ''c'' instead, then he produces a safe connection.
Similarly in this classic tesuji, ''a'' doesn't work for black, but ''b'' does.
In your example, looking at the two marked black stones, the one on the top side is weaker. So applying the heuristic, your first instinct should be ''a'', pulling the netting move back into a knight's move on the weak side. As opposed to ''b'', which makes the gap on the weak side even larger (two spaces instead of one space) and therefore even easier to for white to break through.