I've been a developer now for a year and a half, and right now, I don't think I would have any anxiety about writing code on a whiteboard (even if the final outcome would be no code - I can't know everything!) or even over the phone. However, when I interviewed for the present job, I was straight out of college, and even with 10+ years experience being a hobby programmer, I was very very nervous. So, I would say coding questions are OK, except maybe for junior, inexperienced applicants.