Yeah, it's the strange thing about engaging post titles - people seem to be so busy answering them, they 'forget' to also upvote them. In contrast, a meme that's funny but about which there's not much to say, is more likely to get an upvote as some kind of compensation for the lack of discussion.
My expectation is that a post's score is upvotes minus downvotes, but I think it should be more like upvotes plus comments with downvotes excluded (or maybe let users filter based on upvote/downvote ratio or something). Maybe count commenters instead of comments.