I think you could try to do the same thing that you are intending, right now. Say you published a post. You then tell everyone to look at the opposing view at "co-publisher's" link, in Steemit. Once rewards have been sent out, look at who has the most rewards, and pay out the difference to the other person. Does that make sense?
That's true. But there wouldn't be a way to split rewards in terms of reputation.