Why not induce the demand and provide a more reliable service that people would actually use? I'm guessing it's been tried and failed? How else are we to break the London-centric cycle that the intercity rail infrastructure in the UK is trapped in? Look at Germany for example; they have excellent transport links between every city without any Berlin-centrism. There is far better balance given that it's not all being funneled into Berlin, but spread out towards Frankfurt, Dusseldorf, Cologne, Munich, Hamburg, Stuttgart, Mannheim, Nuremburg, Dresden, Leipzig, etc. Why can't we have the same for Cardiff, Edinburgh, Glasgow, Birmingham, Manchester, Newcastle, Bristol, Liverpool, Leeds, Sheffield, Plymouth, Brighton, Southampton, etc. Because at present, everything goes into London with diddly-squat left for anything outside of the LSE commuter zone and there's barely any incentive to try and break this cycle!