I mean, sure, that’s a possibility. But some people are just really good at whiteboarding problems and explaining solutions. Sometimes these people end up being technical interviewers. If you’ve been a technical interviewer for a while, you don’t find the experience stressful. After a while of doing technical problems they start to seem easier and easier, even when presented with evidence to the contrary (when candidates find them difficult).

Speaking as someone who is (1) a technical interviewer (2) good at whiteboarding problems and (3) has near zero fear of public speaking, I think the big exercise in humility is to figure out ways to get evidence for the interviewee’s skill set even when it’s dissimilar to my own.

It would be weird, because we rarely whiteboard people.

We've found that the three best predictors for good hires are Curiosity, Ability to Self Learn, Ability to Listen.

Good hires will generate fill 2 or three.