Would it not perhaps be a good idea to have such a scenario to deal with on a training day?
Is training really necassary for that though? I thought miming and doing actions is what us Brits are famous for. After all, how many times do we see people abroad asking for the bill with the obligatory scribble in the air. I've certainly used your tac-tics before. Some feel a bit self conscious doing it but if it gets the message across.