ChibiPooky
Yay hockey!
It's not my opinion that you need to limit variables and have "controls" in experimental situations. That's how science and data work. If you have faulty methodology that doesn't account for variables then the interpretation of the resulting data will always need to be couched with caveats about its accuracy. There are many who don't want to do that, and that's what I mean with the hammer analogy. It may be better than the stick we were using before but it's still not right for everything we're trying to do with it.
It's how science works, but it's not how real-world data works. Real-world data is dirty as hell. The whole couching with caveats bit is a lot more about the data than the analysis in this case. And because of the number of events we're working with, cleaning the data takes away a lot of value.
And just because it's not perfect doesn't mean you don't use it. You use it while understanding how it's not perfect while looking for something better. And if you don't have a stat guy, you're probably neither using the "stick" to its full potential (or maybe even correctly) nor looking for a better one.
Do you really think these stat guys are going into meetings saying "this guy has 45% Corsi so he has to go" or the like? Your whole argument seems to be motivated by the idea that stat guys are basically message board fans with influence. They're not.