I get the idea, but then I'll be doing the work that the SVG engine is currently doing. So really, here you're trying to get canvas to do something that it wasn't designed to do - which is weird, because that was your argument against svg in the first place. A quick google reveals the general solution of "sounds like you should be using svg." [0]

Given that svg 100% works for my usecase, I don't have any reason to attempt anything else at the moment. People give svg a hard time about performance and I think that's counterproductive. My suggestion is that everyone should give it more of an honest shot and I suspect they'll find that there are plenty of cases when it becomes the first tool they reach for.

[0] http://stackoverflow.com/questions/19284304/how-redraw-on-ca...