There is a tesuji that I have seen in a number of joseki as an example of why a certain move does not work.
Now I understand that the tesuji works by threatening snapback, but can't the defender make trouble by playing a in the diagrams? Or, to be more precise with my question, how should the person using the tesuji respond?
This has been a problem for me where I cannot put the stone at a in a ladder because the ladder does not favor me in the small nadare.
I cannot play b because the ladder does not favor me.
zinger: In this diagram could be at c. The extra stone noted by Bill makes this sequence not really work for black.
Imagist: Ah, that makes sense, and now I understand why my opponent played there.
zinger: In this case, works. After , cannot profitably escape. White could also play at a, which eliminates aji on the outside, but leaves some on the inside (a black cut at ).