See the link below, I either live under a rock (not totally out of the question) or this is a really good idea. The plow in the video has two edges, the standard on the front of the blade for pushing snow forward but also another edge on the back of the plow that floats when you're going forward and when back dragging snow, it hits stoppers that essentially give you a second wear edge for back dragging snow (the one in the video is a rubber type edge, I believe). Good idea, now let's see how puts on on there Cub's first!
https://youtu.be/6-d_MBrsER0?t=1m25s