Yep, it's still slow/jerky (although it does seem that disabling relativenumber helps a little bit). I have no idea what the problem is. It could be that I expect perfectly smooth cursor movement, and I'm just not getting that for some reason.
Did you try using `:set ttyfast` ?
You say "smooth cursor movement". Can you elaborate? What exactly is "slow"? When the screen is scrolling? When the cursor is moving? Spacebar will move the cursor one character forward in normal mode, and follow newlines. If it is the cursor, is it just as choppy if you hold the spacebar?