I think this is on the right track. The best interviews I've been a part of involve the interviewer asking a question they don't fully know the answer to. Then

I think this is on the right track. The best interviews I've been a part of involve the interviewer asking a question they don't fully know the answer to. Then the interview turns into a conversation where both parties are trying to work together to formulate an answer. The candidate should be scored based on how constructive that conversation is.