I've been on mid-day trains from Pok that have several closed cars, and as the cars fill up closer to the city, they'll open up more cars. It's never really bothered me, execpt that it makes the cars more densely populated.
Also it's a process to remove cars from a consist. Think of all the things that must happen. (In this example, I'm talking diesel cars) First, the consist has to be taken to someplace where the cars can be stored, and then you need to cut off how ever many cars. But, you have to make sure that you leave a cab control car at the south end. Since many times there is only one cab control car, you'll have to do a switching move to pull the middle cars out of the consist. This will one take a fair amount of time, and leg work of uncoupling cars and resetting up the brakes, but how much of an advantge is there? Also, how many times do these trains only make a one way trip with closed cars. Say a mid day train from Pok to GCT with some closed cars then turns to an evening train with all cars open.
Eric
KE5BAX
Obligatory Simpson’s reference:
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