I have been doing some experimentation with rail layouts in OpenTTD, and quickly realized that two rails side by side all the way is not very good. I have found that short stretches of two rails with the rest of it being one rail to work for me. Despite this, I still wonder if there is any better way?
Over long stretches of straight rails between two stations, what is the most efficient way to run two trains? Let's say its 150 squares away, and it will just be those two trains. Most efficient would have the highest cargo per minute per train car per dollar.