Funny, I've never heard of anybody bringing an airplane home safely because they DID have 2 receivers installed. Never, and I've been flying on and off (mostly on) for 20 years. I've never seen someone safely land because they had control of half the control surfaces on their airplane.
Well, here you go then.
A friend of mine brought his H9 Extra down with only the right side of his plane functioning. It wasn't pretty, but he did get it down in one piece. He was lucky that the side that was still functioning also happened to be the side the throttle was plugged into.
I have been flying since 86 and I have to say this is the only time I have seen a two RX system save a plane. I run single RX myself. And so far, all of my crashes have been either dumb thumbs or structural failure. In those cases I don't care if have 30 RX's in the thing! It isn't going to help.