About 7pm on Thursday, 16-JUN-16, Park Street, upper level: a "C" train pulled into the Boston College berth on track 2. No announcement was made for anyone who wasn't expecting it. Less than 20 seconds later, a "B" train pulled into the Cleveland Circle berth on track 1. Both trains sat there for a minute or two as passengers boarded. Somebody obviously made the decision to do this shuffle, why can't they be bothered to make an announcement for those that don't look at the rollsign? And since "B" trains are supposed to loop at Park Street, how did it get to track 1?
There are two separate systems on the trains: The AVIs, which control switches and the automated announcements, and the headsigns. The C train had some reason to be on the alternate track - perhaps it was short turned at Park. The B meanwhile had been extended, perhaps to cover for a late Lechmere train. When it got to Park, it would have been routed onto the wall track (using an AVI code that just controls the switch but doesn't change the announcement) so that it didn't have to wait for the C.
The sign/announcement system is still being developed; I don't know too much about that process but I suspect further improvements will be on the way eventually.
