One reason consists might not be shortened right now.... where would you put the cars?
In one of the towns near me, our commuter agency usually stores four trains overnight for express services. They switched to a reduced schedule last week, and today I noticed that two of the four trainsets were still tied down well after their normal departure times.
Amtrak doesn't have a whole lot of layover space in most of their terminals, let alone storage yards, so it's probably easier to keep the consists intact than it would be to try and find storage space for them.
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