Thanks for clearing that up. Even though I have one myself and have hung it in torrential rain, I am always sort of amazed at how dry I can keep things by just using the stock tarp and SS. It always LOOKS to me like rain will blow in from the sides at each end, especially if I don't have the extra protection of the SS undercover. But so far it never has on the few times I have put it to the test. My worse case result was about a tablespoon of water lying harmlessly in the bottom of the undercover, following a all night storms with nearby tornadoes, heavy wind/rain and even hail.
For I consider that the sufferings of this present time are not worthy to be compared with the glory that is to be revealed to us....that the creation itself also will be set free from its slavery to corruption into the freedom of the glory of the children of God. For we know that the whole creation groans and suffers the pains of childbirth together until now.