This is what I use, and honestly it (and other systems like it) is the only thing that allows some conversations to progress if someone doesn't reply for hours or a day, depending on how much I've been commenting. I've had a random reply to a comment of mine that came in a week later yield a useful conversation.

It also means I can just ignore HN for longer periods even if I really want to know if there's been movement in a discussion I've been having. Seeing if there's an email present is less distracting and time consuming than reading through my threads.