Would it be possible to get {{subst:REVISIONID}} to work? I.e.,
{{REVISIONID}} displays the current revision id, but there's no way to
capture it in time.
Can {{subst:REVISIONID}} work, or would that be too weird for the system?
If not, PREVREVISIONID would be very helpful; to allow you to stamp
articles with an edit. (I'm working on Template:GFDLSource).