Today I've written some code to help throttle back Skritter's graphics demands when low framerates are detected. My problem is that despite grabbing the oldest of the old laptops around here and loading it up with other programs, I can't get Skritter to run slowly enough to identify performance bottlenecks. So I can't figure out what would be helpful to turn off when things get slow. I'm talking about CPU-slow here rather than network slow, so not about slow-loading pages, but about choppiness on the practice page.

There is one sort of choppiness that I can reproduce, and unfortunately can't do anything about: if you have too many other programs or tabs open, they can periodically cause all Flash and JavaScript execution to stutter. (So when you're writing, your cursor momentarily pauses and it messes up your squig).

But apart from that, what else can make it slow? Are there any particular types of animations that it slows down on?

(You can press Ctrl+Alt+F to turn on the framerate monitor -- look at the little 41/42 monitor on the the top.)

Firefox + opened Outlook Express or Outlook 2007 on my ASUS EEpc makes skrittering viertually impossible. If use Chrome, then better. So, maybe for someone effect is just a little, and one can't identify outlook - skritter bad relations. This is my 5 cents. This is also on XP.
However, on my office PC, with Win7 and Chrome, (and also Firefox), Outlook does not harm to speed at all