White-boarding or "oral exams" are effective in proportion to the skill of the person giving them. Most people have little natural skill in this even (perhaps especially) if they are expert in the domain being examined.
I learned this rather well studying abroad in Ireland. I got a final grade of 92 in a class on protein modeling, which in the UK/Irish grading system is really high.
The professor asked me if I had taken the class before.
I hadn't, but the exam was all short answer and multiple choice. Which was very different from the long-form work most of his students did, but absolutely in an American student's wheelhouse.
I was okay in the class. What I was really, really good at was the test.
White-boarding or "oral exams" are effective in proportion to the skill of the person giving them. Most people have little natural skill in this even (perhaps especially) if they are expert in the domain being examined.