Yeah, I'm certainly not opposed to the hypothesis that Google's culture had nothing to do with their success, it was just product-market fit and good timing. But it's a commonly told story - everyone praises (or praised, for a while) "Google-style" interviews, Laszlo Bock's Work Rules! was pretty popular, etc. And it's a selling point for startups that they have Xooglers who are bringing in that culture; if Google's success is just "launch the right product at the right time," the fact that you have a random former Google employee should be as relevant as having a random former Yahoo! or Alta Vista employee.