I've mostly managed to avoid JFK and use ATL or MSP to connect. Back in the 90s DL had parked two CRJ700s next to each other, one going to "Dallas" the other going to "Dulles". With the overarching jet noise it was hard to distinguish the two (There was no signage) - after asking the ground staff (who were pretty gruff and unhelpful), I managed to get on the "Dulles" flight. Several other run ins with staff proved less than customer friendly..