I find it surprising how little use is apparently made of CV's 3 and 4. For 'road' traction that has to move heavy trains, 50 is about as low as I start. Values in excess of 150 in CV3 will deliver a good representation of a steam loco starting an unfitted freight at the heavy end of its load rating, picking up one wagon at a time at below walking pace so the guard isn't thrown off his feet, then gradually grafting up to the usual circa 20 mph line speed.
I am regularly disappointed at exhibitions when DCC operated locos snatch an unfitted freight all into motion within two seconds, and are running at circa 20mph within a train length.
Seeing such an operation at one show on a very well modelled layout, and the DCC system in use was Lenz which I have, I asked whether I could demonstrate what was possible. The loco was already programmed so it ran at scale for 20mph at speed step 12. I used PoM to set CV3 to 180, then resumed control and started it away by entering speed step 12. Predictably enough it smoothly and slowly eased into motion, and went away gradually grafting up to line speed. Opinion was violently divided. One of the exhibitors was most impressed. The other three wouldn't consider it: why would we want to do that?; we exhibit to drive the trains...
