So I go to code A, invoke Eclipse's "Extract Method", and *poof*, I have a new method. I go over to B, to replace my copied code with a method call...
... and it's already been done for me.
On the one hand, that's exactly what I wanted. OTOH, it's kind of spooky. It hadn't even occurred to me that Extract Method would go looking for duplicate code and refactor that as well. It's probably usually correct, but managed to hit a button I wasn't even aware of -- the "Waitaminnit, that's *my* code! Don't screw with it!" response was quite visceral...