I don't know if it's still true, but the system used to let you either comment or downvote, but not both. That is, if you replied in a comment any downvote to w

I don't know if it's still true, but the system used to let you either comment or downvote, but not both. That is, if you replied in a comment any downvote to what you replied to would not be counted. Always struck me as a bit of a misaligned incentive, but I've always had many concerns about the way karma is used/applied on this site.