I signed up for this and am pretty certain it said there was a control group attached to it (which says to me that none of the vids I wanted removed would be if in that group). Well, none of the things I wanted removed were, so I opted out of it. But when RReporter installed it apparently removed the old YT menu which had 'Not Interested/Don't Recommend Channel' and the opting out didn't restore it. I used that menu a lot and haven't found a way of getting it back. So I got less back from opting in than I had before. Didn't work for me. Hope it did for someone else.