>Most people know that if they move to a new address, they have to give a
>Change of Address notice to the Post Office.  What is happening here
>however is the poepl haven't moved, but the Post Office decides to rename
>their street, without telling them.
 
I don't agree with this analogy. The reason why sys admins typically don't
tell their users the address has changed, is that users can still _receive_
mail sent to the old address. So, admins can't imagine there would be any
problem. They don't realize that for a mailing list the _outgoing_ address may
be important.
 
So, it's more like the Post Office printing a new return address on the back
of your envelopes, not realizing some people use it to authenticate the
sender. Talk of a stupid analogy :-)
 
Nicolas