I love it when this happens - I so enjoy watching to see who the cabin crew will chose to question first.

They normaly revert to type, and ask for the boarding pass of anyone vaguely youthful and then they tend to go on what people are wearing.

I enjoy it so much when they get to me - which is normally pretty early on in the process - if I am feeling really naughty I mess about tryign to fing a boarding card for ages (this lulls the cabin crew into the belief that they have found the culprit) and then just wjen they are about to move me anyway, I produce the boarding card and if it is BA they see they were just about to boot a "VIP" - such fun! and normally worth a bottle of Champagne to take away as well. heehee

Nick