A couple questions:
Seems a bit harsh, unless you're on a slow connection? If it's the same as FF, that's in ms, so 2 seconds instead of 0.25 (default). I can see slowing it some, to reduce CPU load, but I'm thinking 1000 seems better. Else, if your page takes 2.01 s to arrive, you wouldn't see the final thing until 1.99 s later, or am I understanding this wrong?

What are these doing? I googled briefly, and found people using them to speed FF up, but no explanations. Are there docs somewhere on this stuff?

Everything else made pretty good sense to me.