That is indeed it. Several Amtrak regional-corridor routes overlap with commuter-rail service: MBTA (Boston), Shore Line East (New Haven), Metro-North (NYC), SEPTA (Philadelphia), MARC (DC - Baltimore), Virginia Railway Express (DC), Metra (Chicago), Sounder (Seattle - Tacoma), Metrolink (LA), Coaster (San Diego).
The proposal contains roughly 21 existing corridor services and 30 new ones. I say "roughly" because some of them are ambiguous in some way. Of the new ones, 13 run in existing long-distance routes, 7 in former Amtrak routes, 8 are new routes, unless one counts pre-Amtrak routes, 1 connects 2 Canadian cities (Windsor - Toronto, Windsor is across the river from Detroit), and 1 is that existing commuter-rail line (LIRR).
Regional corridors using long-distance routes may not be as strange as it might seem, because that how some existing ones got started, like the Capitol Corridor and the northern part of the Pacific Surfliner.
At least one route was originally an Ambus route: Stockton - Sacramento of the San Joaquins.
The newer and expanded corridor routes got that way because of support from the states that they run through. So which new ones get started and which expansions get done will depend on the vagaries of states' politics. It's something like local rail-transit systems -- their development is very patchy, with some cities being several years ahead of neighboring cities.
The proposal contains roughly 21 existing corridor services and 30 new ones. I say "roughly" because some of them are ambiguous in some way. Of the new ones, 13 run in existing long-distance routes, 7 in former Amtrak routes, 8 are new routes, unless one counts pre-Amtrak routes, 1 connects 2 Canadian cities (Windsor - Toronto, Windsor is across the river from Detroit), and 1 is that existing commuter-rail line (LIRR).
Regional corridors using long-distance routes may not be as strange as it might seem, because that how some existing ones got started, like the Capitol Corridor and the northern part of the Pacific Surfliner.
At least one route was originally an Ambus route: Stockton - Sacramento of the San Joaquins.
The newer and expanded corridor routes got that way because of support from the states that they run through. So which new ones get started and which expansions get done will depend on the vagaries of states' politics. It's something like local rail-transit systems -- their development is very patchy, with some cities being several years ahead of neighboring cities.