many people here still vote by agreement, rather than for comments that are interesting, insightful, contradictory, terse, and so on Given up and down arrows n

many people here still vote by agreement, rather than for comments that are interesting, insightful, contradictory, terse, and so on Given up and down arrows next to a comment, the overwhelming majority of people will always vote based on agreement, no matter what you tell them to do, because the user interface practically begs people to do that. If you want people to vote based on something else, you'll have to redesign the user interface (and even then I suspect it will be difficult).