I can liken it to a police officer at an intersection where there's no red light or the lights are out. That officer directs traffic around to make sure that everything flows in a reasonable and very safe manner. If you look at air traffic controllers, that's exactly what we do—at a much higher level, because airplanes can't stop in mid-air. Everything is very fluid.
That's literally what we do. We're constantly moving airplanes around, making sure they get from gate to gate safely every time.