You seem to have a very different perspective on downvoting than myself, and I would guess most of the site users. Downvoting is not primarily a message to the writer of the post, it's a message to the rest of the site that says "I don't think this post is worth reading." It seems pretty strange to characterize that as passive-aggressive. It might be if it were all about a communication between the downvoter and the writer of the post, but it's not.
]]>It might be necessary to examine whether rank opinion polling really makes such a good fit with mathematical reasoning.
]]>Furthermore, I think the real issue here is that saying "have some courage" could easily be interpreted (remember, this is the internet) as incivil, or at least near the lower bound of civility on MO. In fact, this comment was flagged as potentially offensive, which is what brought this thread to my attention. Let's set aside this issue as a example of a being misunderstood on the internet, and just thrash out the "downvoting without commenting issue", if it needs that.
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