Anyone can be a doctor or lawyer too. I know what you mean, I think, but I don't know if I buy the distinction. There is a formal pass-the-bar testing event for lawyers. For nurses and I believe doctors there are boards. Same basic purpose AFAIK. They take these tests when they are just entering the profession. How meaningful are they years later, compared with the experience gained in the interim? My wife is a registered nurse working in cardiac critical care for seven years. If she interviews for a new job with that employment record behind her they aren't going to ask her what an aorta is, which is sort of the equivalent of what Asana is talking about doing here (and what everyone does, to be fair).

So you seem to be saying that a professional nurse, as an example, can be trusted to know the basics after seven years of work, because he or she was required to take a hard test on graduation. But a programmer with seven years of experience must prove that he or she knows what a binary tree does? It's also worth pointing out that lawyers can get people jailed or cause them to lose their property. Doctors and nurses can kill them. So can we, occasionally, but it's rare.

The most effective interviewing technique, as far as I am concerned is to send the candidate out for lunch with a few of your engineers and tell them to find out whether he knows what he's doing. You spend an hour talking software with some people and it's awful hard to fake knowing your stuff.

you'd be surprised at how many programmers with seven years experience have no freakin clue what a binary tree does!

There is a reason fizzbuzz is phenomenal filter.

fizzbuzz does not filter for programmers capable of doing original, thoughtful work in a realistic work environment.

A developer (in a non-pathological work environment) has time to discuss and research a solution.

FWIW I don't remember the last time I had to implement a binary tree since my C++ course in college; I'm not a fan of pop quizzes in interviews, but if you're going to do them then at least make it relevant to the work you do on a daily basis.