> It's interesting to note that this method is in the range of 20 times 
> faster than using a standard lineto.
>

There's a situation in Quickdraw and OS X I think where repeated 
commands lose speed because of some dirty region accumulation and 
flushing going on...

I think you can turn off or modify the buffer copying or region 
accumulation going on such that Quickdraw draws everything to one dirty 
region before flushing the whole thing finally, thus avoiding like 
50,000 mini-flushes or regions along the way. Some tecthnote I read...

Such might be one cause at heart of the sloth noted. But regardless, 
you'll always be faster drawing direct to memory, which is what pixel 
peeking and poking is doing. It's the graphic equivalent of using a 
pointer to move all over a text handle and set things about or not, 
quickly.

Robert