I think you could actually get them to accept a new strategy with open arms, where everybody needs to have some Google watcher process installed that checks and reports back what you do with the search results (I don't think unless the target website imports Google JS scripts too it can't track any more?) and more specifically, your body reaction to see how you feel. "It's necessary for better search results!"
They could have let Chrome users rank any page they're browsing to get quality feedback. The installed base is massive.
That would just be gamed like everything else. Downvote the competition, pay SEO folks to rank your stuff high, etc
It would be quite costly to pay millions of people to do your bidding when you're competing against millions of real users.
Right, they just care about the 10 minute captive audience bit and how many ads they displayed in that time.