at one point they made the paint delay adaptive, but i never checked how much
the pref may still limit it, i dunno.
i was on a connection the other day where only the title showed and the rest of the page was blank, and i suspect that was the same sort of issue bodqhrohra had. it looks like it didn't even bother painting.
i'm gonna have to remember to try it again and see if setting to no style helps, next time.
(also see how slowly the data is coming it. i forgot to check)