Induced demand/congestion is the argument I would use against expanding/enhancing road capacity. You improve the infrastructure, more people drive and you shift the choke point but with the problem that you now have more cars/more congestion/more pollution.
Also concerned that grand plans get put forward, but as planners start facing cost overruns (kind of inevitable in London) you get a watered down solution which does even more damage than the original plan.
Induced demand/congestion is the argument I would use against expanding/enhancing road capacity. You improve the infrastructure, more people drive and you shift the choke point but with the problem that you now have more cars/more congestion/more pollution.
http://en.wikipedia.org/wiki/Induced_demand
Also concerned that grand plans get put forward, but as planners start facing cost overruns (kind of inevitable in London) you get a watered down solution which does even more damage than the original plan.