Do not allow traffic lights to be blamed for planning failures

As much as I detest traffic lights in most cases, there are times where traffic lights simply cover up a major planning issue and where our energy needs to go into the underlying planning problems that require traffic lights rather than hoping a simple removal of lights will make all things wonderful.
An example? Priors Road in Cheltenham, one of those large Wimpey Homes developments on the site of the old GCHQ (apparently this was going to be even bigger originally) and somehow the planners have allowed a single access road to access these hundreds of houses and flats plus a supermarket. A single road for how many thousand people?!
Now unsurprisingly, there are a set of traffic lights at this junction since that many people can simply not get into and out of the estate easily without congesting the main road but the problem is not the lights, it is the original plan and worryingly, a council that approved a plan which lets a single road feed hundreds of houses.
Surely a planning law must require a limit on how many people can be served by a single road, especially now that most people have a car. If the development cannot connect in 1 or 2 other places to another road, the planning application is denied. Simple as that!
This country has become a magnet for cul-de-sacs because people have this utopian view that cul-de-sacs are havens of peace lacking all the terrible through traffic but in reality, lots of terraced streets and parallel roads make life much more pleasant since there becomes many routes to the same place and not the need to funnel all the traffic onto one road complete with traffic lights, calming schemes and complaints from local people that it's hard to cross the road.
Hmm!