It is my opinion the flats were included in the consist to distribute the weight of the engines and
avoid this time consuming maneuver.
While that might seem logical, it was not the case. I was told the flats were going to the top of the pass for some MOW work, and they were, indeed, dropped off atop the pass and the lead locomotive ran light back to Chama.
I've not seen this consist or anything like it repeated since, and doubleheaders up Cumbres (which were run reasonably often after this date in '04, and even more commonly in '05 with 488 coming back on line) are still run as true doubleheaders on the C&TS.
I would hazard a guess that running in this configuration would be a tricky proposition, but that's just an amateur's under-educated opinion. Someone who has real experience and knows what they're talking about might comment.
Scott