While visiting St Louis back in 1964, I caught the section crew getting ready to clear up. St. Louis was home base, and I believe this crew was responsible for inspecting and maintaining between Paines and Elwell. Some railroads used to give these light motor car operators a lineup of trains and they were on their own to get in the clear. No so on the C&O -- the dispatcher had to protect all M of W movements. Of course in CTC this was accomplished by blocking controlled signals. In train order territory, the work area was blocked off by putting out "hold" orders at open offices, or issuing "Do not pass (specific location) without permission of train dispatcher" orders.