What is something you used to believe, preferably something concrete with direct or implied predictions, that you now know was dead wrong. Was your belief rational given what you knew and could know back then, or was it irrational, and why?
Edit: I feel like some of these are getting a bit glib and political. Please try to explain what false assumptions or biases were underlying your beliefs - be introspective - this is LW after all.
You are confusing two different sources, the one that mentions FizzBuzz and the one in your link. Although both sources use the number 200, they are using it to refer to different things. It is the former (which uses it to refer to interviewees) which I object to, not the latter (which uses it to refer to resumes), except insofar as the latter is used to try to prove the former.
No I'm not. The Fizzbuzz article cited above is a wiki article. It is not based on original research, and draws from other articles. You will find the article I linked to linked to in a quote at the top of the first article in the 'articles' section of the wiki article; it is indeed the original source for the claim.