The blogger is to be frank an absolute dumb nut! He is not losing more viewers. In fact he is gaining them. If people upvote your video and it goes onto a social network site that is outside of your "youtube channel" that just means that you are turning on automatic sharing. Ofcourse, an option that lets the user who is upvoting to choose whether he wants to share it or not is all that is needed.

If he does share it, that just gives your video and even greater probability of going viral. Why cant content publishers get this?