A relatively high proportion of students at elite schools will be in the top 1% of the IQ distribution (and the same is probably true of HN contributors), but I

A relatively high proportion of students at elite schools will be in the top 1% of the IQ distribution (and the same is probably true of HN contributors), but I don't think you have to interpret this literally for GP's post to be clear. Intellect, like driving skill, can be measured along enough axes that more than 1% can be in the top 1%.