I've been an interviewer in Google for quite a few years now. I know my favourite question inside-out, implemented it in a couple languages, know the theory behind the advanced follow-ups for theorists, know the realities of running this down to the wire level for applied folk... I always answer "sure, let's assume that" when the interviewee suggests a clarification. Just makes for a smoother interview flow. If what they suggested is out of bounds of reason (say, round trip time to the moon in 10ms), I'll just note that in the report.
