As always, if I didn't comment to an entry that you made (and it's been more than 48 hours since you posted it), then this means that there was no concensus made about whether the change was necessary, a consensus was made and it was decided it shouldn't be changed, or it's something that requires the faqadd priv, which I can't do. :)
[link] FAQ 187 updated to include a note that e-mails should be sent in plain text, and that you can't set "Don't auto-format" but you can use <lj-raw> if you don't want your e-mail post to be auto-formatted.
[link] FAQ 20 updated to include a link to FAQ 15 (deleting comments).
[link] FAQ 3 updated to say that comments to a deleted entry are made inaccessible.