I know it may seem like everything's horribly broken right now, but from an insider's perspective on an extremely high volume website and application, I swear it's not us.
All the javacript stuff we do is to maintain compatability back to IE5 Everything seems redundant because we're forced to re-impliment html5 components because that's what we promised in our SLA. In fact, our google analytics for today shows several hundred IE5 users on our application.
I mean, it works. It's not the most effective/perfect, but it doesn't need to be. This isn't like back when we had to make sure everything worked with 512 mb of ram.