Well I wonder if a response even has to be public.

I guess I feel like I only comment if I have something constructive to say. So that little bit of feedback about why it wasn't useful would be nice for me. I don't mind if no-one else has to see it.

I've been modded down for wondering wtf I was modded up, so don't feel too bad. see thread at http://news.ycombinator.com/item?id=249009

Comments about moderation rationale can clutter discussion, so maybe they wanted to discourage them. (A form for reasons when moderating would probably do well to keep them out of the way unless requested.)