Well that is interesting like one of the comments said, happens with model trains as well…
Shades of earthquake mode in reverse!
I think if I were sitting in that locomotive cab being constantly nudged while sitting at a signal or something? Not sure if I could take it.
What’s the big deal? Non-event!
If the engine is kicking you while stopped, something is seriously wrong.
A lot of units surge when in pacesetter with a really light load. There was one spot on one of our loading tracks where everything would do this, it was in a dip and the train would suddenly accelerate as it became balanced over the hump just before this point, which the units would respond to by dropping their load and rolling back into the train. Then the train would stall, the units would start pulling and the cycle would repeat itself.
You can try to mitigate this by keeping the independent brake moderately applied to give the power something to work against and prevent the units from rolling back when they drop their load, but it doesn’t always work perfectly.
Tricks of the trade.