My favorite one was the guy who looked up my name on a list of resumes he had printed out from LinkedIn or something and asked me why I was in such and such a role when I was clearly more suited for another role based on my experience. First of all, he was wrong, and second, creepy!
Just in general, be respectful. If you disagree with an answer, ask a clarifying question or move on. Don't tell me in the middle of an interview that out whole approach is wrong, especially when it's on a fairly subjective matter. We're doing the interview to learn about each other, not to convince each other about development philosophies. If you don't understand that there's a time and a place for disagreement, it's a warning sign to me (not saying disagreement is bad, but there are times when it's much more appropriate than others).
Just in general, be respectful. If you disagree with an answer, ask a clarifying question or move on. Don't tell me in the middle of an interview that out whole approach is wrong, especially when it's on a fairly subjective matter. We're doing the interview to learn about each other, not to convince each other about development philosophies. If you don't understand that there's a time and a place for disagreement, it's a warning sign to me (not saying disagreement is bad, but there are times when it's much more appropriate than others).