I'd just like to say, using this approach, and by treating them with some respect, atleast when they are within ear shot, I have had little chav problems, and even when they are getting roudy with friends have said "nah leave him alone he hasn't said anything".
The people who seem to have the most peroblems with them are the sort of people who looks down on them, to their faces, and talk to them with such resentment, and allways take the piss even when talking face to face. These people have got in to fights been mugged and generally harassed.
I dont want to get dragged down into the argument, asll Im saying is theres way round trouble with these guys in most situations.