I know Admins can assign users to groups. But...I trust our users not to misbehave, and would like them to be able to opt to join/leave a group themselves - not neccessarily on registration - just as something I can include maybe as a menu item or a 'Join One Of Our Groups' page/link. Is this possible? I ought to say - I'm hopeless at PHP, so the moment anyone says anything about hooks, filters, classes etc - I'm lost. A shortcode would be neat :)- I can manage them!