I expect it would be more able to cleanly cut through the bodies or throw them out of the way with more momentum. If it’s going slow it’s more likely to ride up on top of a body. Anecdotally, I’ve heard that derailers tend not to work on fast moving trains.
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Depends
Not if the track is perfectly straight.
Removed by mod
I expect it would be more able to cleanly cut through the bodies or throw them out of the way with more momentum. If it’s going slow it’s more likely to ride up on top of a body. Anecdotally, I’ve heard that derailers tend not to work on fast moving trains.