marking the mainline with oil droppings

In my Pan Pastel collection today, I noticed a dark grey color (called Paynes Grey Extra Dark), and tried brushing it on the center of the mainline track in Everett's Bayside yard, with good results, shown in the photo below. The long train is in the siding, with the main track to the left of it. It makes the mainline look heavily traveled when compared with the adjacent yard tracks, which will help operators keep track of which track is which. Try it, you'll like it. I've definitely seen this done on other layouts. It's a nice subliminal clue to which track is the main track. Using an airbrush might be better, but not easier.

By the way, the first car in that train is one of the new Rapido NP boxcars, relettered for the BN, by Tim Taylor, using decals from the Northern Pacific Railway Historical Society. The prototype cars were used in MOW service and were painted solid brown, but we liked the NP heralds so much we just changed the reporting marks for 1973. I guess I should find another Pan Pastel color to fade those heralds way back. That is (should look like) an old car! Another day. First, I have to now put oil droppings on the rest of the mainline...