The fast moving hotshot train was overtaking any trains along the way traveling Westbound on normally Eastbound track. Hotshot trains carry perishable and high value freight such as UPS next day air parcels. These trains must not be late as if they do, millions of dollars in refunds and fines will be paid. As such they have priority and will pass any trains that get in their way. God forbid any trains that hold up that one. This catch only happens once or twice in a lifetime. Not only do the trains have to be at a certain speed, at a certain place, and a certain time. But you must also be standing in that unknown space when one train ends and the other begins.