Agreed. It wasn't at all what I was expecting him to say as I read the first part of the article. What I thought he was going to say was this: the normal distribution is only the prior -- what you would get if you hired people randomly. Hiring is difficult, of course, and there is inevitably a certain amount of randomness in the process, but once you have culled the low performers once -- or succeeded in not letting them in in the first place -- you no longer have a normal distribution, and you shouldn't act as if you did.