This is a great use of technology and programming/diffs to both cool and useful ends. I wish all my agreements, insurance policies, etc had something like this cleanly through one place. Maybe a policy standard for just that so companies make it public that way and no copyright problems. Also, companies eventually not doing it would be seen as devious.
[I work at Docracy, prepare for a plug!] Well note that we have a great negotiation and e-signing service that uses these same diff tools, try it out! http://www.docracy.com/supersigning
