Lot of debate about how to control windage in a crankcase, but take a garden hose and spray a piece of screen wire and see what it does to the stream of water, same idea with that screen. But then what is the best size mesh? and does the oil cling to the mesh and effectively close off the holes if to small, or let too much oil pass if to big? I personally like the idea of the screen windage tray, I have built a couple, but I have no data to prove one way or the other how well it did or did not work, and to my knowledge no body else does either. If someone does, that would be a good post to read.