[smt88]

Even if a developer did need to implement a binary tree, she wouldn't be doing it in a high-pressure, interview setting, nor would she be doing it using a marker on a white board.

Furthermore, the business value of a programmer is rarely how she writes code in isolation. It's how she writes code on a team. I'd take a B-level programmer who is excellent at writing clean, readable, simple code over someone who is a savant at white-board problems.