mephisto - yep it's one of those weird protocols that totally defies logic esp given the newly married spouse probably does not hold the necesary security clearance ........(in this case I'd proabably want to say no to the jump ride anyway) - sidebar: guess we need to really watch out if Osama & Co announce it's Ok to date Cabin Crew!)
As for CC seats - even 'assist seats' that do not have primary door responsibility, our group would not release for pax or even qualified crew on non duty travel.
I just subscribe to the worst case theory - if it doesn't make it over the fence then why have the risk of an extra untrained body in the way of a primary door