All the roads I worked with in those days required the shipper/reciever to specify the full route when the car was billed out. This was worked out through a broker in most cases. There was such a thing as "brokers routes" for lumber. A shipper would load a car with lumber and bill it out with a route that shipped it to a destination in the direction the broker thought the car of lumber would sell. The route usually covered an odd circular route that was often difficult to put in the computer and just about the time you got it entered the lumber would sell and the broker would issue a diversion that would then have to be entered instead of the original route. In the old punch card days, you could burn up a lot of cards before the car finally got a real destination. When the bankrupt Rock Island tried to make itself over, one of the slogans it painted on its bright Blue cars was "Route Rock"---an effort to get shippers and brokers to route their shipments via "The Rock" (an attempt, somewhat successful, to become a bridge route). "Broker's Routes" were used for other goods, but was most common in the lumber industry.