So you are saying there is no evidence that road schemes boost the economy, I'm sure there must be plenty of evidence around to suggest that workers and freight lorry's stuck in traffic queues is a substancial cost to the economy. Yes I would agree we cannot continue to build roads endlessly but that doesn't mean to say that we cannot improve existing roads or build new roads such as the new link road around Lancaster to target specific problem areas, I think it's also very clear that many Businesses choose to locate their businesses in area's where there are good roads.
If I take the village where I live for example there were 2 railway line within reasonable distance of the village although neither of the stations on the line were particularly well located both being on the edge of the village. The most useful to put back would be the one to Leeds however that route is so well built on that it would be impossible to put back and you would likely need a knew alignment for much of the route and frankly the cost of it I expect would be huge. On the other hand Low Moor station has reopened about 3 miles from where I live. Now its not much use to me from the point of view of travelling to Leeds or Bradford but I did use to travel to Preston the other week, and in the grand scheme of things the cost of reopening such as Low Moor is small compared to the cost of reopening new lines so perhaps that is what should be concentrated on.
Now near to Low Moor station is the Spen Valley route there have been discussions on here before about reinstating this line, it does have the advantage in the route is essentially intact and no doubt it would bring some benefit to Cleckheaton and Heckmondwike but even with an intact route the costs are going to pretty high. The route is also heavily used as Walking and Cycling route and any attempt to bring it back may not be universally welcomed, and if was brought back a Light rail Tram/Train solution might be the better option. But even if you spend the money on that line its still not much good to me as live nearly 3 mile from Cleckheaton so I will still need road transport to get to Cleckheaton, and will still likely use road transport to get to Leeds or Bradford from where I live.
You seem to be of the view that we can solve most of the transport problems of this country by building new railway lines all over the country, well apart from the cost of it being huge, not practical for some parts of the country, it simply isn't going to happen, and apart from anything else as a country we are road orientated, and if you held a referendum as to whether or not HS2 should be built it would loose by a massive majority, if you held a referendum on whether we should build HS2 or a new North South Motorway I reckon the Motorway would win by a massive majority.