[adamc]

I used to do this in interviews -- give people problems not because I cared whether they got "the" answer, but because it gives you a chance to see their brain work.

The problem with this is that many, many interviewers do this badly. They think they are looking for someone who gets the right answer. Or they are not good at assessing how other people break down and analyze problems.

It is artificial. All interviews are artificial. This is why everyone would prefer to hire candidates they already know a lot about. But a good interviewer isn't looking for a perfect performance.