Here is a proof of concept for Deedii for using the native comparison feature, as well as a structure which (maybe) better articulates what I was talking about.
It will work in both 2003 and 2010 (have not checked 2007, although I think it should work). The major difference is that in 2003, you would be forced to save two documents before completion (just save to desktop and delete afterwards-- code could easily be added to delete those "temp" files)