The Swedish program Nova on SVT showed how things worked at Borlänge marshalling yard, a fully automated yard. One man can drive the engine and just drop the cars to the right track.
http://www.akerstroms.com/bilder/Film/Nova.html
There are two more big marshalling yards i Sweden, Säve (Gothenburg) and Hallsberg, but there it takes three persons to operate the trains. But all three have coils to brake the cars.
(Hope this was the right place to post it)