At first I thought was the diesel really necesarry? Then after seeing how many cars they had 1000 tons probably was a litte much for the 475 by herself. 475 was probably working harder than she had for alot of years. The switcher was working a little too, maybe in the 4th or 5th notch.
@ Scott Brown Some preserved steam engines do not have air brakes, and it is the reason why some diesels are brought into the equation. They power the air brakes on the rolling stock, and they also give some support when needed.
I only major issue with this is at 14:50 when you were zoomed so far out. I would have loved to see the train close up as it would begin it's forward motion and then slowly zoom out as it began to make it's way forward. It would have added a more dramatic effect.
Hey! This is the exactly the same famous steam locomotive that played as Rainbow Son! In Thomas and the Magic Railroad! Haven't seen it for a long, long time now.