Having had the chance to do some interviewing over the last few years I think the most important thing on my side is to know what I'm trying to test for with any particular line of questioning. I don't always see that level of self-awareness in fellow interviewers. (The worst is the sort who say "if they don't do X when I'm asking for Y, I'm going to score them down." Do they really care about Y then?) What exactly is gained by letting the candidate go off into the deep end for several minutes before they realize on their own, if they ever realize at all, that their initial approach was bad when it should be a simple question? If the purpose of a calendar question or fizzbuzz question (or my own initial coding question, "implement is_even") is to answer "can you code?" why does it matter if the solution isn't that great? If you have an answer to the question you can follow up with things like "can you code a better solution?" to distinguish passes, but interviewers should keep everything time boxed, there's other stuff to cover with such short time slots as 30-60 minutes. I like to test some sort of presence for knowledge about regexes and recognizing an application, so I borrowed Yegge's phone number regex question from his phone screen tips, and I'm happy enough if the person realizes that "there's some sort of pattern thing to do this" because that's a google away, happier if they can write a script that uses regexes correctly, happiest if they know or get close to the grep incantation, but if they start trying to write their own parser I'm going to stop them because that's going to take a lot longer than 10 minutes, especially if I say "oh yeah there's another number format we need to extract". But that person still might be a good hire, just not knowing about regexes at all. By keeping things time boxed I can make sure all the other areas I care about are covered and can judge if certain strengths can compensate for certain weaknesses.