Other railroads own the tracks (capitalism - because they built or bought them).
Amtrak uses the tracks through the graces of the owners. Amtrak passenger trains have last priority.
One should always make schedule calculations based on this and adjust arrival times by 10 - 20% of the trip total.
I ride the Surfliner from San Diego to Los Angeles. Service is usually pretty good. I would rather be on the train drinking a cold beer as opposed to being on the freeway. Sometimes people commit suicide by sticking their heads on the train tracks and that screws things up. I wish they would not do that.
Other railroads own the tracks (capitalism - because they built or bought them).
Amtrak uses the tracks through the graces of the owners. Amtrak passenger trains have last priority.
Amtrak schedules and freight schedules are exactly the same as the trains of the 20's, 30's, 40's, 50's and 60's prior to Amtrak taking over all passenger operations. Their New York to/from Florida passenger service is exactly the same, to the minute, as the Seaboard Airline's Orange Blossom Special and Atlantic Coast Line's The Champion.
Those timetables were established to allow passenger trains prime use of the tracks with freight taking over odd hours when the mile long freight trains would most benefit from reduced crossing traffic allowing for faster freight movement. Speed limits for freight are higher during off hours than during daylight hours.
Amtrak, through inefficient central planning and bureaucratic bungling cannot follow the timetables as private passenger trains used to do and thus freight takes precedent as they cannot allow their schedules to be disrupted by the inept operations of a government boondoggle.
Passenger trains, including Amtrak, have always been given the best time schedules for their needs and freight only takes precedent when passenger cannot operate on a regular time schedule.
To blame Amtrak delays on freight traffic is on a par with Obama blaming Bush for everything Obama's ineptitude has caused.
Perhaps you define "graces" differently than I do. They pay to use those rails and are therefore at the mercy of the contract they sign, not the good graces of the owner.
Rail cargo is not generally high-priority stuff, but they do have to pay to have the train underway.
Rail lines do have to be repaired and up north summer is the time for doing it.