If I see a comment that says close to what I would've said, I upvote it. Then, I inspect that comment's parent. Notwithstanding whether I agree or disagree with

If I see a comment that says close to what I would've said, I upvote it. Then, I inspect that comment's parent. Notwithstanding whether I agree or disagree with substance of the parent comment, I parse it for tone and intent, and if I detect respectful tone and benign intent, I upvote it because it contributed to the discussion (by prompting a thoughtful reply). I recursively apply this strategy for all comments.