I read the code gist that someone else posted earlier...can someone explain to me exactly why this is gross in the first place? I can easily imagine a scenario

I read the code gist that someone else posted earlier...can someone explain to me exactly why this is gross in the first place? I can easily imagine a scenario where someone innocently added this code with good intentions (i.e. purely for performance data that sites can use) as opposed to being evil. It may be the case that there wasn't enough internal review of the code in question, and that's all. Also you have the ability to opt out...