I really struggle with the concept that some programmers cannot write FizzBuzz. I'd expect it from someone who has finished their first programming unit.
I've known some programmers that I expect might not be able to write FizzBuzz in the time allotted within an interview, based on how long it has taken them to produce code 5-6 times as verbose as needed given the simplicity of the task at hand.
It's related to the assertion that fewer than 1 in 100 programmers is unable to write "FizzBuz" in the programming language of their choice.
The rate may be statistically insignificant amongst all programmers, but what is the rate amongst programmers looking for a job?
Different question :-)