Sorry all, this isn't going to work, because the HN account I created is too rate limited in responses. I've now been waiting 43 minutes to be allowed to make the next reply.
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I'm not cherry-picking responses, posting the first thing that it says.
Still trying to improve the prompt. Here's my current one, but it seems to get confused that the comments and replies should be distinct and not part of an ongoing thread: https://pastebin.com/DKEuZSrP