I actually did that a few times. I obviously didn't say that :) But a couple times, after putting up with a whiteboard exercise, when it was my time to "ask q

I actually did that a few times. I obviously didn't say that :) But a couple times, after putting up with a whiteboard exercise, when it was my time to "ask questions to the interviewer" I ask them to also solve a problem on the board. I remember one who completely refused, saying that he wasn't the one being interviewed, so I just left. The other 2 did it, failed, and I never got a call back :) That being say, I definitely try to evaluate my peers as much as possible during interviews, but it's usually based on what they ask, how they react to someone disagreeing with their positions, stuff like that.