Say you ran a small server with a couple of 2 hour home movies (in avi format) from your recent European vacation. Your friends and family all had speedy connections so there was no reason for you to accommodate 56K users (sorry dial-up folks), would you need to split the movie into several little RAR files.
I really don't see how this could possibly improve the speed of the download (a mb is a mb afterall) so why do it? Why not just leave the flicks in AVI format so the end users can just watch them as is, and needn't worry about missing or corrupt RARs?
I've noticed the RAR method of distribution with other personal holiday video FTPs and wondered if it the best way to upload them to interested parties.