In this context, is HN Replies something other than the reply button?

I review my post history to see replies.

I use "I check my threads page sometimes and comments that aren't on the first page cease to exist as far as I'm concerned."

I think many of us don't worry about whether someone answers us in a thread. Fretting over how a thread went after you said your piece doesn't improve the goal of HN: curiosity. If people agree with your comment, there is no need to jump back in. If they disagree and you jump back in, it just feeds arguments. When you do say something, do it because you feel you have something worthwhile that adds to the conversation. Do not comment just to promote your own voice. And once you have said something, move on.