Supply, demand, house prices and neighbourhood plans

I was reading a report about the impact of new housing development on local house prices thinking that this would provide evidence that increased supply would have a deflationary impact on house prices. In fact the research, commissioned by Barratts (the UK biggest house builder), the London School of Economic AND Political Science and the Home Builders Foundation, was intended to measure whether harm caused by new housing would be reflected in prices in the neighbourhood.
Specifically, the research found:

• House price changes in the surrounding streets and the broader three/four-digit postcode districts suggest that new developments may stabilise or even increase prices in the immediate areas once development is complete where the market is generally stable and rising. They also suggest that there is almost no evidence of longer-term negative impacts.
• For sites where a high level of opposition was experienced throughout the planning and construction processes, this opposition tended to decrease once the development is completed. In one case where there were high levels of opposition, at least half of all eventual purchasers of the new homes previously lived within 5 miles of the development.

I know that building 300 houses is more likely to have a local impact on amenities and services than on a housing market spanning many districts, but most development in this country will continue to be incremental (the volume builders are unlikely to get much over 130,000 units a year) and not  at a scale to be market changing.  Planners and politicians (caught up in a maze of second-guessing) continue to claim that new supply will lower prices (or at least slow down increases) but this research indicates otherwise.

And secondly, an update on neighbourhood planning, or specifically the NDP for my village.  The Plan has been backed up at referendum and waits to be formally "made' by the LPA.  Meanwhile an application for 73 houses has just been approved by the LPA, on a site which was allocated for approximately 65 dwellings. Not much wrong with that.  However, 13 of these houses comprise a ribbon of development into open countryside towards the neighbouring town when the Plan supports development that does no such thing. There are no (that is zero) one or two bedroomed properties for private sale or private rent despite the Plan showing that these should predominate.  There are nearly 3 parking spaces per dwelling, despite the Plan requiring a Travel Plan (only to be submitted after full permission is granted) showing how traffic would be reduced - fundamental to the prospects of any further development taking place in the village (there are two other allocated sites) in an area where congestion makes it less sustainable for existing residents and businesses.  Astonishingly, this was not a case of an LPA overruling the Parish Council (or an appeal decision) but one where the PC supported the grant of permission in these precise terms.

Lessons?  LPAs must supervised NDP preparation knowing that the policies are sufficiently precise to determine applications.  Planning officers must read the NDPs but understand that they are public domain and the Neighbourhood Forum/PC has no privileged rights in its interpretation. And finally, if the NF/PC negotiate with landowners and/or developers they must be extremely careful not to prejudice the determination of any subsequent application.