From what I have seen it is difficult for any user to know what exactly has
changed in the document, a simple solution to this would be to enable the track
changes in the tools menu (MS WORD) and save the document, this way when they
open the document version 2 they would be in a position to see what changes have
happened to the document, this is just a suggestion as I am yet to try it out.
In case it works/ fails please keep me posted.