Better luck than me. I hit a small-ish rock coming off a drop that smashed the whole thing off the hanger and folded it into the back wheel, taking out about a dozen spokes in the process. It was like an explosion - took me a minute to even figure out wtf had happened. It would have been salvageable by replacing the mounting bolt (that sheared off) but it also broke the cast aluminum bit around the b-adjust screw 
