When interviewing people I usually push until I get the candidate to answer "I don't know" on SOMETHING, just to see if they can do it. Not everyone can, and a lot of people will happily come up with a technical word salad to hide their perfectly understandable ignorance on some obscure technical problem I just came up with. That way you get to hear how they ask technical questions. Asking questions is a valuable (an…
That's a trick question. Trick questions are bad because they test interviewing skill and not programming skill. It's a trick question because you want the interviewee to answer something different (I don't know) than what you're asking them to answer. Confident applicants might feel up to saying they don't know, but nervous people who are very self conscious in an interview setting may respond completely differently…
The ability to ask meaningful questions is a big part of any programming job. And (in my opinion) harder to learn than any particular technology.