He's partners with Joel Spolsky, whose old article on hiring [1] set the stage for a lot of the modern hiring era. Even though almost all of the questions are considered unfashionable today, I think the gist of "find any excuse not to hire" still holds in a lot of people's minds. The more people you reject, the better your candidates are, right?
The weirdest about Joel's method becoming the gold standard was that FogBugz around that time (I last used it around 2004) just wasn't that great. It was clunky, weird, and required a Windows server. It was served through a browser at a time when presenting GUIs through the browser was a slow and tedious string of refreshes.
Trello and StackOverflow are so much nicer now than FogBugz was then so I guess he hired better people. But I think a lot of his advice became vogue more because he was an entertaining writer than a great software entrepreneur.
[1] http://www.joelonsoftware.com/articles/fog0000000073.html grep for "no hire" just to get a feel