I think what bothers me about this is that it's an analogy which crosses the digital divide. On the physical "train" side of the analogy, we've got a believabl

I think what bothers me about this is that it's an analogy which crosses the digital divide. On the physical "train" side of the analogy, we've got a believable scheme to save money by only having a toilet in every other car. Given the constraints, it is indeed clever to make these two-car atomic units and reimagine them as symmetrical. All the fixes in the story taken together could pale in comparison to the cost of putting a toilets all the cars. But when we cross the digital divide we get a completely different set of constraints. Even if dealing with 100 million train cars it may be cheaper to just fork the entire train yard and add a toilet object to each car.