I think the explicit goal should be to develop discussion strategies that kill the mindkiller i.e. put people into less tribal and more open minded moods. A good one is "what are people you dislike right about and people you like wrong about?" If you say "I dislike global warming skeptics but they seem to be right in certain things", you are killing the mind-killer, because you are putting people out of the "I like you and your ideas, therefore I think you are right" mood. So one tribe will think "cool, this person thinks we are right" and the other "cool, this person dislikes the same people we do" and all pay attention.