This is how trains are supposed to run... High speed typically takes single track. One delay causes countless more delays.. domino effect. By using single trac

This is how trains are supposed to run... High speed typically takes single track. One delay causes countless more delays.. domino effect. By using single track, any deficiency is immediately visible. So by moving to the surface any potential for error which could be hidden or diluted, each part of the machine is forced to move at the same rate. This increases system wide efficiency.