The same sort of thing happens in NYC. If I see a crowd that's larger than normal trying to pack itself into a full train, odds seem to be about 90% that the next train will be significantly lighter, AND that it'll show up pretty soon.
I think the reason is that the first train to show up is delayed, so more time passes before it shows up, allowing a crowd to build up. They, then, all try to cram on the train that FINALLY got there because GOD who KNOWS how long it'll take for the NEXT ONE to get here. Meanwhile, 30 seconds later, I'm in a train car with a seat.
(NB: This seems to apply to the B/D/A/C lines in Midtown. As far as I know, the 4/5/6 is always a miserable pack of people doing their best impression of neutronium.)
I think the reason is that the first train to show up is delayed, so more time passes before it shows up, allowing a crowd to build up. They, then, all try to cram on the train that FINALLY got there because GOD who KNOWS how long it'll take for the NEXT ONE to get here. Meanwhile, 30 seconds later, I'm in a train car with a seat.
(NB: This seems to apply to the B/D/A/C lines in Midtown. As far as I know, the 4/5/6 is always a miserable pack of people doing their best impression of neutronium.)