The idea I had in mind was to use rail to haul multiple truckloads off public roadways, kind of a variation on doubles and triples but with 53’ trailers in trains up to 20 trailers. Then use the power unit to spot the trailer at a receiver dock.
PS The operator(engineer, CDL driver, motorman) of this would have to be certified in multiple categories, and be more specialized. In other words the labor on an individual basis would be more expensive, but because your paying one person to do the work of 2 to 10 drivers it changes the cost.
The second that interstate commerce, albeit intermodal, were to play into this - the whole idea will die on the vine. Transit and the bus people that run light rail will never be able to handle FRA RULES on their formally closed system. They won’t be able to hide behind FTA’s lax regulation anymore.
Remember it well.
Tunnels also carry 138,000 volt power cables. Saved ComEd from having to dig up the streets to feed new substations. I also remember going to Union Station and seeing BNSF in “LOAD AND GO” mode. Fortunatly most crews were still available and trains were being brought into the station from the yard to leave and make all stops. I stood and watched the passengers who were used to taking a Naperville express from track 2 or a Downers Grove express from track 12 ask gatemen “what track is the xxxx train on?” and being told get on that platform as they are making all stops.
Given the issues with curves, traffic, and everything else that’s been mentioned, about the only way I see freight working on a transit system would be if containers could somehow be delivered to certain locations for delivery to end customers (ie, stores), or even to the end customers.
This would theoretically get trucks off the road during the day.
The major problem is that the infrastructure for such an operation doesn’t exist. Local transit serves the front door. The freight needs to be delivered to the back door.
Motive power for industries served off public streets in days gone by -
Use a Mk IV road trailer. The one that has both rubber tyres and steel wheels. The advantage of the Brandt power unit is it has a truck fifth wheel.