[johnisgood]

Someone might quote your comment as well upon replying. Should we delete the comment after yours which may or may not contain something you wanted to delete? Should we delete the entire thread? If not, would it not get confusing quickly, as in many cases we would have no idea to what the comments are responding?

[gowld]

HN is a chitchat site, not StackExchange. It doesn't need permanent archival of full-fidelity conversations.