An example of a tombstone squeeze.
PeterHB: Discussion by MrTenuki refers to this superceded diagram:
If white plays at a, black can connect the stones safely in a manner similar to that of Case A. If white plays at c...
And it's a ko ( at e). Sure, white takes first and will most likely win the ko, but why start a ko when you can capture unconditionally?
By the logic of your opponent's good move is your good move, perhaps of "attempt part 2" above should be played here? PeterHB: Suggestion accepted.