I've seen a number of other "movies" done with TS (not Microsoft) that are like that. Suspect that they are done with the "autopilot" mode so the maker doesn't have to sit there and actually drive the train the whole time. Autopilot has various parameters for braking & accel rates, but once at the speed limit keeps it there with constant tiny fiddles, too small & quick for a real human to do. As far as the ballasted bridge track ... I didn't notice that, but it's likely because the route builder either didn't know better or just used the standard track textures for simplicity. As with real movies, one must maintain a certain suspension of disbelief...