Well, I just took a good look at your second photo, Rex.
The car to the right of the coil car is what I was talking about. It seems to be loaded as I described. We don't know the weight of those coils (the thickness of the metal, type of metal, density of winding) but apparently they are light enough to allow 3 over the bolster. Obviously, 3 coils of aluminum (doubt that's what it is) of that size would weigh much, much less than 3 similar coils of tin-plated or galvanized steel.
George