I wonder, how would someone interview a doctor. Asking him more of theoritical questions ? Or asking him to do practicals, which I believe might be completely off the books depending on the situtation :).
Anyways, there are
1) people who pass the interview very well, and cannot perform the duty on the job.
2) people who do fair on the interview, but are very well executors of the duty.
3) People who really become the backbone of the feature, and become the go to guy for everything and anything, they may or may not perform at the interview.