I saw a crew set out a cut on a grade once, and used the skate. I wondered how they placed them, in this case, they set out a cut of about a dozen empty ballast cars. They set handbrakes on the the downhill 4 cars, except the 1st one. They placed the skate and pulled the release rod so the car rolled up a little onto the skate, then spun the hand brake on. Not sure if thats proper, but that was how these guys did it.