Here is a scenario I wish to try.
On the prototype for my layout they operated both Passenger and Freight.
I would like to position all switches so that a passenger train could navigate the loop on the layout and pass every station (there will be 7). Start the passenger train moving at the correct speed and let it go.
Then take control of a freight and move out of the yard with the assigned cars to be delivered to the various industries on the line. The freight engineer would have to be mindfull of the passengers as they took precident.
I think it would be an interesting one-man operating session that could be done in DCC, but never in DC.
Will, I'm no wiring wizard, but I'm sure that that could be done with DC, though certainly not with the ease of DCC. It still ignores the fact that the passenger train effectively has no operator, so therefore no one enjoying the task of running it. I could duplicate that same scenario on my layout, merely by installing a twin cab control system, or I could run it as the layout is now wired by running the freight(s) and passenger train sequentially, as each town has a passing siding at the station. For me, the latter scenario is the preferred one, as I would get to enjoy the running of both trains. Another factor to consider is "control" as opposed to just "running". On my layout, that passenger train would be, like the freight, subject to several speed restrictions (in some areas, speed limits for passenger trains are lower than those for freights, too). DCC will easily run the train, as you note, but I don't think that it will respond to posted speed restrictions without operator input or some sophisticated detection electronics. DCC is overkill for my operating scheme, but perhaps perfect for a layout with multiple
operators.
I don't like the wiring aspect of the hobby, which is one of the reasons it's set-up as it is. My "blocks" are merely areas (passing tracks, sidings, or switching districts) where I can cut the power. A switch or two and a few feet of wire suffice. I also didn't need to run a bus wire for the power distribution. The most complicated wiring that I had to do was to accommodate different throttles into the jacks for the walk-around system, including DC, AC, and PWM systems, and that wasn't too difficult. Sorry, but no sale here.

:-D:-D
Wayne