Doug,
The railroad did have a complete list of photo locations, but I suspect if one were to publicize them, it would only result in more non participants knowing where to go.
As far as people shooting apart from the "herd" as you call them, there is quite a bit of that, but there are also many locations where the best shot can only be obtained from one position. Cresco Tank pretty much requires everyone to bunch up, for example.
The shot that set off the other thread was a photo across the meadows just east of Chama, where a fence provides the foreground element. When the drone skimmed along between the photo line and the train, it destroyed the shot. The poster had scouted that location out the day before and was set up well before the train left Chama. He was upset and rightly so. 20 people could stand shoulder to shoulder there and all would get a great photo, but if one person flies a drone in front of everyone, the drone gets the shot and no one else does. That is the crux of the matter as far as I can see.
Michael Allen