You know what, that might be a very good idea, if encoding speeds on my really crappy hard-drive weren't under a second. But no I do see where you're coming from, and for larger files that concept does apply, but blockframe wants to protect your files from circumstances that you can't control, and the concept is still, have the file as its own entity, and to keep it planted, we use RS to make sure nothing funky happens. Small files do tend to cause random access speeds, that's why they're not split up.