The original idea for groups seems to have been as a way to note the
address book lookup key that was used to retrieve the addresses,
I don't think so. I've been under the impression that groups came from
a convention used in paper business correspondence (like interoffice
memos) to indicate to recipients "why" they were copied on the
correspondence. ("why" as in - you're being copied on this
correspondence because you are a member of the Foo board, rather than
because of some other hat you wear)
Keith