This is one reason I'm not too upset when distribution terminals are built with rail connections (as a planning condition) that aren't used - at least they are there when if are needed. As discussed on another topic recently, Castle Donington is one of these.
Quite right. If new developments were built with no thought of future rail connection that could be seen now as a very poor business decision in light of the road haulage trends you describe, and conspiracists would be claiming things were being deliberately made difficult for rail.
Whatever the facilities provided in a freight customer siding complex, the most costly and difficult part to organise is usually the signalled junction connection onto the main line network. If that can be provided or safeguarded as part of a development this makes the eventual adoption of rail haulage achievable within reasonable haulage contract timescales instead of having to wait for the next resignalling in five or ten years. The recent transfer of a host of sites formerly owned by individual freight companies to Network Rail could open up rail freight activities in those areas which in most cases have existing signalled mainline connections, and although some have not been maintained and track may even in some cases have been partially removed, at least the junctions are catered for in the signalling controls and can be restored to use fairly quickly without a complete new design being required.
It could make sense to try and encourage the clustering of distribution terminals around such existing yard complexes sharing their main line connections. The open access that NR ownership implies means the operators of such terminals, usually supermarkets or their logistics contractors, could seek the best offer from the rail freight industry for rolling stock and haulage rather than being beholden to the ways, means and commercial attitude of the particular company that happened to inherit the yard facility during the botched privatisation disposal process.
Some terminals built shortly after opening of the Channel tunnel were built primarily with a naive expectation of each of them accepting full length intermodal trains direct from the continent for forward distribution by road. In most cases that kind of traffic has failed to materialise, I think mainly because of the logistical impossibility of arranging full length trains at an attractive frequency for each single terminal. DIRFT is a notable exception and interestingly has also become the hub for the supermarket domestic distribution chains too.
