HN is best suited to short-term, many-to-many conversation. We're rapidly reaching the end of both of those constraints, HN itself has technical measures to discourage deeply nested threads, and I really do prefer email for long, meandering dialogues anyway.
I wouldn't be opposed to either or both of us posting the rest of our dialogue online, in verbatim, once we were finished, but I do think this is an ill-suited forum to actually continue our discussion in.