Confined to specific routes on existing, unalterable railroad tracks, passenger rail services sharing routes with freight trains are among the least adaptable of transportation modes or types. Aspects of poor adaptability include route limitations, lower quality conditions of freight rails, shared and restricted rights of way, dated technology and unrefined service, as well as, a pervasive inability to implement safety improvements and procedures.
Already causing disruptions and inefficiencies in the basic freight transport operations of railroads, passenger train services operating on existing railroad tracks can impose few, if any critical changes to railroad networks or technology. Introduction of passenger trains operating at twice the speed of freight trains onto existing track systems tends to press and exceed the limits of safety equipment, vehicle crossing gates, warning lights, traffic controls, pedestrian protection and other safety measures that have historically maintained reasonable levels of safety between railroad operations and other activities.
Metrolink, and to a lesser extent, Amtrak, are caught in a double bind between the need to rapidly modernize their rail technology, performance and safety; and the antiquated states of US rail service and industry. Notwithstanding nearly universal recognition of the need for fundamental upgrading and modernization of American passenger rail systems and services, US rail industry is simply incapable of producing a new generation of passenger trains equivalent to international state of the art systems and technology. Any comprehensive improvement in US rail systems would most likely be dependent upon imported technology and rolling stock, adding little to the domestic rail or US industrial economy.