What gives you that impression? If we're talking about the same thing, rate limiting occurs when you post multiple comments right after each other. It will usually make you wait a minute before the next post.
This doesn't happen to me often, but does happen when I comment in rapid succession.
Honest question: why is it sad? There’s another thread[0] going on here right now about how human processes shouldn’t manage pathological cases with policy and procedure. Moderation is all about pathological and edge cases. Mod actions that work on some users every time may not work at all on others. I don’t believe treating us all the same is the best way to get quality discussion, and transparency is not an end in itself outside of government.
So how… how would a moderation log and strict policies make HN a better place?