This is getting funny. But you are right Lee, everyone doesn't want to look like a fool at these big op meets that I go to, so they don't ask. Because heaven forbid that you not know what a term is in front of all the operating muckety mucks.
Rule G was once a must break at the "Sippin' and Switchin' Society" that I played with. Single malts and trains... ahh the good ol' days. Not much switchin' going on then.
OS'ing is short for On Sheet. When you report your train at a specific station (a job actually done by the station operator in the days of yore by telegraph to the dispatcher) you were put "on sheet" at what ever time you passed through. It was a way of keeping track of trains on the main.
____________________ Steven B.
Humboldt & Toiyabe Rwy