Thread Commands
---------------

`T k'
`M-C-k'
     Mark all articles in the current sub-thread as read
     (`gnus-summary-kill-thread').  If the prefix argument is positive,
     remove all marks instead.  If the prefix argument is negative, tick
     articles instead.

`T l'
`M-C-l'
     Lower the score of the current thread
     (`gnus-summary-lower-thread').

`T i'
     Increase the score of the current thread
     (`gnus-summary-raise-thread').

`T #'
     Set the process mark on the current thread (`gnus-uu-mark-thread').

`T M-#'
     Remove the process mark from the current thread
     (`gnus-uu-unmark-thread').

`T T'
     Toggle threading (`gnus-summary-toggle-threads').

`T s'
     Expose the thread hidden under the current article, if any
     (`gnus-summary-show-thread').

`T h'
     Hide the current (sub)thread (`gnus-summary-hide-thread').

`T S'
     Expose all hidden threads (`gnus-summary-show-all-threads').

`T H'
     Hide all threads (`gnus-summary-hide-all-threads').

`T t'
     Re-thread the thread the current article is part of
     (`gnus-summary-rethread-current').  This works even when the
     summary buffer is otherwise unthreaded.

`T ^'
     Make the current article the child of the marked (or previous)
     article (`gnus-summary-reparent-thread'.

   The following commands are thread movement commands.  They all
understand the numeric prefix.

`T n'
     Go to the next thread (`gnus-summary-next-thread').

`T p'
     Go to the previous thread (`gnus-summary-prev-thread').

`T d'
     Descend the thread (`gnus-summary-down-thread').

`T u'
     Ascend the thread (`gnus-summary-up-thread').

`T o'
     Go to the top of the thread (`gnus-summary-top-thread').

   If you ignore subject while threading, you'll naturally end up with
threads that have several different subjects in them.  If you then issue
a command like `T k' (`gnus-summary-kill-thread') you might not wish to
kill the entire thread, but just those parts of the thread that have
the same subject as the current article.  If you like this idea, you
can fiddle with `gnus-thread-operation-ignore-subject'.  If is is
non-`nil' (which it is by default), subjects will be ignored when doing
thread commands.  If this variable is `nil', articles in the same
thread with different subjects will not be included in the operation in
question.  If this variable is `fuzzy', only articles that have
subjects that are fuzzily equal will be included.