Unfortunately, I don't recall seeing what class of routing or how it was determined in any paperwork that the crews had. Never asked any of the clerks or agents either. All we had was a computer print out of the train consist with car numbers, what is in them (or empty or residue for hazmat), tonnage, axles, tonnage profile, where they originated, where they're going, and via what interchange, etc. We had extended information or separate MSDS print outs for all of the hazmat that required them but that's about it.
Back on topic, CSX was actually the worst to get a train from because they used dot matrix printers (you know the very faint text with the holes on the perferated sides of the paper) for their train consists. By the time we got the train out of like Buffalo after the set offs and pick ups they did not only was the print impossible to read but they were cut up and added to so many times you needed a PHD to figure out what order and what was in your train. The rollby ended up being as much finding that out as anything else.
CP had the best paperwork, easy to read stuff from a Laserjet. However if the crew did not leave the paperwork in the knuckle or the yard office good luck getting the dispatcher to give it to you. We wasted hours waiting for paperwork from them.