Andre hit the nail on the head. In addition, the D&RGW had NO signals on the narrow gauge, NO automatic switches, and operated on "flimsies" or Train Orders ONLY! Not to mention the fact, that to my knowledge, no D&RGW narrow gauge car ever had roller bearings, and a "hotbox" or burning oil in the axle housing was a serious issue with wooden cars. Which explains why you see so many passenger trains with a caboose.
For the narrow gauge guys, you can imagine how small and cramped those cabs were, and having three people in there must have been quite a tight fit.
I'm rather curious as to what those "toolboxes" on top of the cabs of the D&RGW locomotives were for, they seemed pretty unaccessable, and tended to appear and disappear in various photos of various locomotives. You know, C&TS and D&S should sell tickets for a ride in the "doghouse." I'd imagine a lot of people would pay good money to ride up there!
Thanks! Robert