The self-voting feature we were discussing only applies to posts not comments.

Voting yourself routinely on comments is questionable since comments usually don't get that much in the way of votes and rewards, and each comment vote uses the same vote power as a post vote. I only do it when I feel my comment is particularly important and I want to promote it, but in that case it isn't for the rewards, it is for visibility.

However, there are some users (I'm one of them) who don't post very much but are active on comments. They may feel that their comments are useful and a valuable contribution to the discussion, so worthy of rewards. (I'll leave it to others to decide if my comments are valuable.)