I have decided that the next time I find myself in charge of a Team Foundation server, or more precisely in charge of maintaining a TFS process template, that I will introduce a Work Item status of "Nuh uh". This status would be almost exactly like a "Re-test" status, but without implying that you have actually fixed anything. Instead, the implication is that the system in question works perfectly fine the way it is, and that the QA tester is, in fact, horrribly mistaken.
I think it will be very useful. But I’m sure the testers will immediately come back with a request for a "Yuh huh" status to counter it, and the whole team may spiral into some very childish behavior. It should be quite entertaining.