Gary, thank you for sharing your knowledge on everything apple!
I recently became a member of a large group. I’m trying to export contacts from a CC field in apple mail into last import in apple address book, so I can then easily select all contacts from the last import and drop them into the new group. I don’t believe a smart group would work since there is not a unique aspect of the contacts. Manually dragging and dropping contacts from all contacts in apple address book into a group would take an unbelievable amount of time. I’m confident you know a better way!