Re: Corbyn's broader and more useful aims?
"with houses filling both sides meaning it's impossible to develop the next bit of land out as there's nowhere to join on an access road."
Part of a new estate's development can involve buying up existing houses to demolish for an access road. If it is considered an essential development then the local council can authorise a compulsory purchase.
The important thing about planning permission is that, in theory, it stops someone building a tanning factory in the middle of a housing estate. It could also stop your neighbour covering the whole of their back garden with a 20 story block of apartments. That is however not guaranteed to be stopped.