Metro's Polite Cattle Call

Here's John Catoe, the new general manager of Washington's Metro system, in an interview with the Washington Post Express, on the subject of riding the rails to work:

Overall, my commute has been good. Of course, a couple of times I've been caught in delays on the rail line. I've talked to the head of rail about the need for the train operator to provide more specific information to the passengers of a delayed train. For example, what do you mean by a short delay?

One thing that's amazed me on my commute is the etiquette practiced by the customers during boarding. Everyone is very good about waiting for the train to unload before boarding. It is great to have that cooperation and it helps us keep the trains moving on time.

Why exactly does such behavior "amaze" Catoe? At most stations during rush hour, passengers have no choice but to wait for others to exit the train before boarding. Otherwise, there'd be no room at all Metro's cattle cars, in which the concept of personal space is a distant memory.