Given the total distances, there isn't as much of a difference as you think. AMTRAK's current direct Detroit-Chicago rail route is 281 mi (452 km). Chicago to St. Louis is more different: current rail distance is 284 mi (457 km) (and target time for the line
after partial upgrades to up to 110 mph is 4h).

A comparable full HSR line would be France's first, Paris-Lyon: 432.5 km station to station, only two lightly frequented rural intermediate stops, non-stop time 1h57m with top speeds limited to 270 km/h on part of the distance.

Ann Arbor is basically a suburb of Detroit

18 miles is far enough to justify a separate station, could be done in 15 minutes by rail.

you see nothing between there and Gary, Indiana

I mentioned South Bend. But there is no reason to not keep at least half of the other current AMTRAK stops: Jackson (again just the city proper populations: 36,000), Battle Creek (53,000), Kalamazoo (77,000), Michigan City (33,000).

Toledo would be out of the way for that trip

As with the lake bend, that counts for little. By current rail distances, Chicago-Toledo is 234 mi, Toledo-Detroit 58 mi, total 292 mi (470 km). If a proper HSR line would be built, at 300 km/h, the Toledo alignment would mean a loss of just 3 minutes and 36 seconds. Much stronger detours have been justified with the extra demand (for example Madrid-Burgos via Valladolid), and the Toledo route would also mean a great cost saving in sharing tracks with a route to Cleveland and beyond. Indeed if you check the two earlier full HSR proposals for a Chicago-centred network, both route via Toledo.

If there is only an upgrade, however, then, given the significant local demand along the direct route (see above), upgrading both lines would make sense. And indeed that's what you find in the current plans for the Chicago Hub Network.


_{*Lunatic*, n.
One whose delusions are out of fashion.}