>>>>> "Lars" == Lars Magne Ingebrigtsen <larsi@gnus.org> writes:

    Lars> Brian May <bmay@csse.monash.edu.au> writes: to it, do you
    Lars> get the complete header, including this Xref line?
    >> Yes.

    Lars> Find the article you want to `^', and then eval the
    Lars> following:

    Lars> (deffoo nntp-request-article (article &optional group server
    Lars> buffer command) (nntp-possibly-change-group group server)
    Lars> (when (nntp-send-command-and-decode "\r?\n\\.\r?\n"
    Lars> "ARTICLE" (if (numberp article) (int-to-string article)
    Lars> article)) (debug (if (and buffer (not (equal buffer
    Lars> nntp-server-buffer))) (save-excursion (set-buffer
    Lars> nntp-server-buffer) (copy-to-buffer buffer (point-min)
    Lars> (point-max)) (nntp-find-group-and-number))
    Lars> (nntp-find-group-and-number)))))

    Lars> Then `^'.

I hope I did that correctly...

    Lars> This will make Emacs pop you into a debug buffer that will
    Lars> tell you what `nntp-find-group-and-number' guessed.  If the
    Lars> guess is wrong, go to the " *nntpd*" buffer and see what's
    Lars> there.

below is the debug buffer - I can't see any calls to
nntp-find-group-and-number nor can I find a *nntpd* buffer.

I don't know where it got -1 from.

The parent article has the following headers:

Message-ID: <ulg0xfx53p.fsf@wahoo.princeton.idaccr.org> 
References: <wk66ydmkja.fsf@home.net> 
NNTP-Posting-Host: wahoo.princeton.idaccr.org 
X-Newsreader: Gnus v5.6.45/Emacs 19.34 
Xref: towncrier.cc.monash.edu.au gnu.emacs.gnus:31448 

(("gnu.emacs.gnus"))
  (progn (debug (if ... ... ...)))
)
  (if (nntp-send-command-and-decode "
?\n\\.
?\n" "ARTICLE" (if ... ... article)) (progn (debug ...)))
)
  (when (nntp-send-command-and-decode "
?\n\\.
?\n" "ARTICLE" (if ... ... article)) (debug (if ... ... ...)))
)
  nntp-request-article("<wk66ydmkja.fsf@home.net>" "gnu.emacs.gnus" "newsserver.cc.monash.edu.au" #<buffer "*Article*">)
  gnus-request-article("<wk66ydmkja.fsf@home.net>" "gnu.emacs.gnus" #<buffer "*Article*">)
  gnus-request-article-this-buffer(-1 "gnu.emacs.gnus")
  gnus-article-prepare(-1 nil)
  gnus-summary-display-article(-1 nil)
  gnus-summary-select-article(nil nil nil -1)
  byte-code("¬