And this entire argument would be done and over with if railroad movement rate, food/shield/trade bonuses, and maintenance costs simply
were adjustable in the editor!
Standard Out-Of-The-Box Game:
RR movement factor: 0 (=infinite)
RR improvement bonus:
--- irrigation: shields:0, food:+1, trade:0
--- mine: shields:+1, food:0, trade:0
RR maintenance cost: 0 (=free)
And if you thought railroads are fine as they are then, well, fine: you leave the settings as they are. But if you wanted a little variety you could have:
RR movement factor: 12 (=each move costs 1/12 point)
RR improvement bonus:
--- irrigation: shields:0, food:0, trade:0
--- mine: shields:0, food:0, trade:0
RR maintenance cost: 10 (=10 railroaded tiles cost 1gpt to maintain)
And everyone would be happy.
"Change if you want, don't if you don't."
And don't forget the scenario makers! Consider:
Change the name of "road" to "dirt road" and "railroad" to "paved road" with appropriate graphics and in the editor do:
road movement factor: 2
railroad movement factor: 4
and voila, you have now two grades of roads for your scenario set in the Middle Ages...