>>1421470>amtrack doesn't really own any track and has to ride on the freight lines, which in turn give priority to their own freight trains.This isn't completely true. Amtrak has priority over all other trains and freight carriers have to pay penalties for delaying Amtrak trains. The problems start when a freight train has a malfunction that ties up the mainline for a while, because even minor train issues involve at least 15"-30" of a delay. Bust a knuckle? An hour minimum, often it can be more than that. Many mainlines are at or near their maximum capacities, which compounds any other delay.
Topography also restricts throughput, if there is a steep hill that puts most freight trains down to 10mph and an Amtrak train is behind it, it's just going to have to wait for the train ahead to clear. Dispatching can prevent that sometimes but because of congestion it can be unavoidable at other times.
Also, track speeds aren't conducive to passenger trains anymore. There was a time when superelevated curves and a handful of track gangs patrolling a territory were the norm, those days are gone. Speeds have dropped due to restrictive curves in some cases and deferred maintenance in others. None of the territories I worked had a stop speed of more than 65mph, and even then that was only for a little while before the max speed dropped down due to bridges, curves, or slow orders. I imagine Amtrak wouldn't consider a corridor with significant stretches of track speeds under 50mph or so, which eliminates some potential routes.
