[Matt_Cutts]

I believe Google Docs keeps all the revisions, so if anyone cares a lot, they could go back and check.

But what I've found with Google Docs is that if someone is making a trivial change (like correcting a typo), they'll just go ahead and make the edit in the doc. If they're suggesting a substantial change, they'll add the suggestion as a comment and let the author decide whether to incorporate it.