Agree entirely with you BEagle - there is never any need to raise your voice or take an aggressive stance. This is always provocative and rarely successful in achieving the desired outcome. Being firm but polite is usually a good way of going about things!
Had a situation about a year ago where a couple of Russian guys had their phones turned on before we even left the runway after landing into LHR. We as crew heard this, so I went out into the cabin to intercept these rule-flouting rascals. I found them both playing with their phones and asked/told them (pleasantly of course!) to turn them off. One replied 'I'm sending a text message'. The only response to give was 'I can see that Sir, thats why I'm asking you to turn the phone off'. He loudly announced that he would do so as soon as he finished his text message and that the sooner I disappeared, the sooner this would happen.
Naturally I wasnt going to let that happen, not as a matter of personal pride (although without doubt that would have kicked in later!) but pax need to know that reasonable requests from crew are to be followed. I told him that it had to be turned off now and he ignored me completely. I had no choice - I pointed out (whilst still smiling) that if he did not turn the offending mobile off I would have to request the police to meet the flight. When asked what he would be charged with, I told him he could be charged with failing to obey the orders of a crew member and having his mobile phone turned on onboard an aircraft, both of which are (and have been in previous cases) punishable by jail (although highly unlikely!)
He took great pleasure in telling me I was talking cr@p until a passenger from the other side told him I wasnt. He scoffed and asked her what made her think she had a clue. It was a fantastic moment when she informed him (without a smile) that she worked for the Crown Prosecution Service! It was one of those rare moments where you realise things couldn't be any better (sad I know!).
My (longwinded) point being - other pax can often help to get your point across. In the above scenario, whilst not grossly serious in the grand scheme of things, that other passengers comments got the phone switched off without having to take drastic action. This is the outcome all of us want, nobody wants to have somebody hauled off an aircraft in handcuffs (not normally anyway).
However, while enlisting the help of other passengers (whether requested or offered) can be useful, it can add fuel to the fire and you can end up trying to end the existing situation, trying to keep the 'helpful' pax out of it and try to stop the whole thing escalating into something worse.
In the Mark I version of this thread, I posted that all round awareness of pax behaviour from the second they step on board can help if things go wrong. This doesnt mean just looking for ABPs who could help in an emergency, be aware of the people who may be most likely to cause disruption and also be aware of those that could help if they do. Its not always as simple as that, but building that sort of awareness day by day will help us all to anticipate situations very early on.
Finally, whilst a minority of the travelling public can be morons, the majority are very pleasant and happy to be on board. If we can all just relax and have a (professional) laugh with those passengers, then maybe the onboard atmosphere will be far more pleasant and it also makes it easier to ask people to behave! Most importantly, it means we can all come home in the evening feeling chilled and happy which has got to be of prime importance!
Safe and enjoyable flying all...
FJ2k