It's not quite as silly as it sounds - Amtrak trains travel at twice the speed of cargo ones. So you have to clear at least half the track before an Amtrak trai

It's not quite as silly as it sounds - Amtrak trains travel at twice the speed of cargo ones. So you have to clear at least half the track before an Amtrak train can enter. But there's no problem running a cargo train after the Amtrak one.