There need be only one train operator per train (or maybe two?), which can carry millions of dollars' worth of payload – which can have dozens of cars. Despite

There need be only one train operator per train (or maybe two?), which can carry millions of dollars' worth of payload – which can have dozens of cars. Despite it being a seemingly more simple and discrete problem to solve, it may not be worth it – a human's judgement can come in handy from time-to-time.