You can replace the buffer stop with an incline too steep to climb with the available traction at which point their best bet is derailment by going too fast around a turn. But again, with properly banked curves the trains simply can’t go fast enough for that to happen.
> You can replace the buffer stop with an incline too steep to climb
There generally isn't the room to plop down hills instead of buffer stops. Instead it's possible to use energy-absorbing buffer stops (rather than the traditional "hard" buffer stops), possibly with e.g. dowty retarders on the track beforehand to force specific speed ranges on incoming trains.
