These items have when crafted are guaranteed to have one property from a list of 4 possible. Two of which are FC/FCR. From what I read these properties can stack with the other random properties. Does this mean if faster casting is the guaranteed property and faster casting is one of the random properties, they will stack for a total of 2 FC? Similairy if FCR 1 is the guaranteed property and FCR 3 hits on one of the random rolls, 4 FCR is achievable? Or are the guaranteed properties simply dropped from the list of random possibilities?