Joseki-related life-and-death example 5

 

White has invaded at the 3-3 point with and Black has blocked with . How should White play next?

Here's the correct move:

 

Here is one sequence for white to live unconditionally:

 

After , a and b are miai for life.

Here's another possibility:

 

Again White lives.

Bad shape

What if White plays this way?

Bad shape  

is bad shape, as ...

Black answers with 4 and, depending on White's response, White dies or, at best, gets a ko. Here are two cases where White dies, followed by the ko case:

 

... is too good shape for Black (hane at the head of two) tderz
Locally White can't make two eyes but the aji of the clamp at a remains.
However, it is painful for White to have to rely on this aji.

 

White has a basic dead shape.

 

White gets a ko

One last example:

 

If the , exchange has taken place earlier then loses its power and is possible.

Variation for Black

What if Black plays this way?

 

This is one correct sequence for White:

 

But suppose Black persists at ?

 

Here is a clever sequence which lets White escape to the outside or else capture two stones:

 

What if Black ataris on the inside instead of playing in the previous diagram?

 

After White will capture something to make life.

Suppose Black knows all this and plays below to defend in sente?

 

makes life and later the clamp at a is not small.