Yep that explains what I had thought above. As for helpers out of Durango to Gato that happened a lot. In the video we are starting work on, 478 was sent to Gato to help 498 back west with loads on 6/5/1968. It had run to Chama(498) on June 4th, while 478 was taking the first loads(Which John West shot) down to Farmington. The footage we have is shot by Richard Traver and there are 2 shots double heading and one of 498 after the helper was cut off for the run down the hill. Sounds like the Durango to Chama line was more of an issue than Chama-Antonito since it was such a roller coaster. At least with the Cumbres line you pretty much knew what you needed for those runs.
Greg
PS Earl-mailing a video to you today