The current system sorts the luggage in a rented cargo hanger. The luggage goes on trucks where it's delivered directly to the resort.
You're suggesting Disney is going to transport the luggage via train, sort it at some location at WDW then truck it to our resorts?
Which system is more efficient? Train cruisetours in Alaska truck the luggage. Tourists go via train and luggage goes via truck.
Quite likely the current luggage system will be kept. On the other hand, which is more expensive -- renting a cargo hangar at an airport, or running your own warehouse/hangar on the copious amount of property you already own?
You can forget about your 2 minute stop if significant amounts of luggage have to be handled, either by Disney or by passengers.
If there is a luggage car, it can be at the end of the train and simply decoupled during the scheduled stop. Ditto,in reverse, for coupling a luggage car going the opposite direction. Plus, I can see the WDW station being an endpoint for many trains during peak arrival/departure time -- not every train has to go all the way to Tampa.
I'm not so sure about Mears getting cut out of the equation. Disney will need to transport guests from the rail station to the resorts. Some guests will have luggage. You might need fewer DME buses, since each bus run will be a little shorter.
If I were in charge, I'd provide a "universal" resort check-in desk at the rail station. Allow people to drop off their remaining luggage, if they like, for transfer to their room, and then proceed straight to the parks rather than have to go to the resort first.
At the very least, activate park tickets and/or dining plans (if applicable), and provide some option for dealing with carry-on bags.
I don't see much (any) time savings if DME is changed from the present direct bus from MCO to a train ride followed by a bus ride.
Time isn't the only factor. There's cost, which is hard to estimate unless and until contact details are known (plus any benefit Disney would recoup by running their own station, but also additional costs).
There's also the "green" issue. If the rail line is going to use less energy and create less pollution, then Disney gains an "intangible" benefit that may not necessarily show up directly in the bottom line, but is important for PR and community relations purposes.