In reply to spenser:
> Are the double yellows not there to signify that parking there is an inherently unsafe thing to do, either for you or other road users?
Also because parking in those areas there tends to cause serious congestion or access problems. With parking on both sides of a road ( think town centres here and small streets) it can block off access to emergency vehicles, like fire engines and if a lorry turns down a street and can't go further it is the start of chaos.
The big problem is working out who has to park there for a very short time and who is taking the piss. Unfortunately many motorists are the latter.
A few years ago all traffic wardens were removed from Aberystwyth (a political decision over who paid for them), without any enforcement mayhem ensued within weeks
http://www.telegraph.co.uk/news/uknews/road-and-rail-transport/8642177/Aber...
And it was mayhem, we sometimes visited and what happened when motorists are given a free hand was very much jungle mentality, quite unbelievable.
Parking restrictions are there for a very good reason, but there have to be some allowances to them, the big problem is working out who, when, where and for how long some discretion is tolerated.