I've edited the post to include this comment (for completeness), but it felt like a good cop/bad cop situation, even if it weren't deliberate. Lots of teams said the same thing. It was probably all in our mind, but it's something that will be in the minds of future interviewees as well (people really build it up for themselves).
In stressful situations, just being asked probing questions by someone you don't know can feel like an act of aggression, even if it's not meant to be. They can sound like a challenge to your authority on your subject matter; I could see how you would feel like it was a good cop / bad cop scenario (which I really doubt it was).
