Very nice mod, anyone undertaking it though remember it will affect your future upgrade patches and make them a nightmare to implement (prepare for lots of coffee and lots of patching by hand) so only do it if your very confident with the system and have a cart you don't intend on upgrading very often.
Remember to BACK UP your site properly before undertaking a mod like the one above.
We use a very similar method in a CMS we've been developing for another project. It's one area where apache servers come in very useful
