The author is ignoring that:<p>A) Most sites do have content with which async GA can load in parallel.<p>B) Where you put the GA snippet is a trade-off. Putting after window.onload will decrease the time it takes to get to window.onload, but it will also lessen the accuracy of your data; especially your bounce rate.<p>C) If you're worried about delaying user visible functionality that is tied to window.onload, you shouldn't be tying that functionality to window.onload in the first place. There are better ways to detect when the DOM is ready to use.
I use my own server side analytics code. The reason I do, is that, no matter how much people pump Google Analytics, I'm afraid of it. I've been to too many sites that were completely hung, and in the status bar, my browser is saying "waiting for www.google-analytics.com".<p>I usually hit refresh and it generally works, but how many people don't? This isn't something that's happened to me once or twice. It happens often enough that I'm consciously avoiding ga. I don't need to cause more people to bounce for no reason.