The "Even Dirtier Secret", HN edition: devs who can't type, don't read books, can't understand LtU or git or BDD, get all their info from Stackoverflow. Oh, yeah, they're not in the top 99.999999%, so now way Joel will hire them.
"You'd be absolutely astonishedly flabbergasted at how many programmers don't know how to READ. I'm dead serious. You can learn to speed read even faster than you can learn to type, and yet there are tons of programmers out there who are unable to even skim this blog. They try, but unlike speed readers, these folks don't actually pick up the content."