It would seem to me that it would be in Amtrak's best interest to NOT force the layover. After all, once A to B is booked, it becomes more difficult to sell B to C on the same train. Similarly, once B to C is booked after the forced layover, A to B on the same train becomes more difficult to sell.
That of course assumes that the passenger can stay in the same room, were the layover were not forced, i.e., that there isn't another rule that forces the passenger to switch rooms.