This is true, but in those cases there is the perfectly respectable "N mistakes I made" format. The thing that rankles me is positive advice (you must do A and B in order to succeed at X) given by people who have just failed spectacularly at X.
Still, I've been part of a couple of failed projects before I set out on my own and I'm pretty sure that I would have fared a lot worse if not for my prior experience. That saved me a ton of time and money.
I still found plenty of 'original' mistakes to make though :)