This discussion has been quite interesting. I think it points out the risks of assuming everything worked by the book on a railroad. What the bosses put out in proclamations were not always followed to the letter.
I worked in the telegraph office of the NYC in Albany, NY from March 1956 to September 1958. At the time there was a lot of internal promotion of the NYC's Pacemaker service in company literature. I also remember a series of messages being fired back and forth between someone in a position in one of the yards and a freight agent at a local town about putting inappropriate loads in Pacemaker cars. The messages were noteworthy in that both parties seemed really upset by the whole thing. It didn't make a lot of sense to me at the time and when I talked with others in the office they just laughed at it as some new hire college kid at the yard trying to everything by the book.
It is easy to visualize a local agent sending a group of cars to a good shipper, some Pacemaker cars for that service and some regular boxcars for shipments off the system. If the customer's wharehouse men get shipments loaded in the wrong type cars, what is the local agent to do when a Pacemaker car comes back from the shipper consigned to an off system location. Does he send it back to the shipper to get it unloaded and then reloaded in the correct car? probably not.
The business had to get done despite the published practices.