The trouble is you're dealing with the public. Some of them are smart, but many are not. Anyone remember how so many pax were gobbing off about the awful cabin crew shouting at them and pushing them down the slide if they hesitated when Virgin had their smokey evac? They are too stupid to realise that the crew are there for their safety and too stupid to pay any attention to briefings or immediate instructions, and they then blame everyone else. Shame these people can't be identified at boarding and sat in seat with delayed release belts that only open when all the cooperative and intelligent punters are out, (if at all)...