I don't understand what you mean. The author said "Despite his confidence, he couldn't even explain what GDP is, which was essential to his explanation." which seems like a perfectly reasonable complaint. If you are trying to describe a concept to me that I don't know about, I might ask you to explain to me a much more basic idea that you are referring to. If they can't explain the basics then all of the explanation of the original subject matter is wasted.
I wasn't asking the guy an exact formula for GDP, but at least some definition of what it was trying to measure. Aaronc's point below is exactly my concern.
As per appeal to authority, I didn't think I was asseting anything controversial. I doubt you are saying it's better to hire dumb people or just ignore intelligence, so I am confused what you're arguing with here.
And of course his "appeal to authority" consists in citing an article from the totally and utterly overrated Spolsky...
Dismissed.