[steveBK123]

Yes, that's my point. One person very much can do it. There are train lines that have their signals & stations setup for this, and the trains prepared for this mode of operations. The MTA keeps caving to the unions so that the trains remain staffed with 2.

[zuminator]

What's more although the train operator (driver) can open and close doors, the conductor (doorman) is not certified to operate trains and thus provides no emergency redundancy except perhaps in terms of crowd control.