As long as users of Google, in your scenario, could continue to view all search results, regardless of moderation, why would it matter? Here on Slashdot we can all view all the posts regardless of the moderation. Negatively moderating the post does not change where it shows up in the list of posts. It's still there for all to see whom choose to see it.
If a user decides to subscribe to the group think of moderation and browse only at +5 they see what they the group wants them to see. If on the other hand a user decides to ignore the group think and browse at -1, they see things as they are. The control and choice is entirely in the hand of the viewer.