That's a great idea...but unfortunately, I don't think it's a particularly
efficient idea for large lists.  Personally, I don't have the time or the
inclination to actively file 700 such agreements (talking about just one
of my lists, ACCESS-L).  When I say "actively file", I mean, every time
someone subs or unsubs, I have to deal with it.  ACCESS-L's set Notify= No.
It's simply more than I want to deal with.
 
On the other hand, I've had pretty good luck with spamming...I have most
of my lists set either Send= Private or
 
* Send= Editor
* Editor= Owner,(listname)
 
I think I forward only 5 or 6 messages/week back to the list, and I <have>
caught at least one spam in the net.  While this wouldn't stop someone from
subscribing, spamming, and unsubbing, at least it makes them go through one
extra step.
 
Just my $0.02...Nathan