(add-hook 'allout-mode-hook
          (lambda()
            (th-font-lock-allout)
            (local-set-key (kbd "C-c C-a C-t") 'th-allout-toggle-current-subtree)))

(defun th-allout-toggle-current-subtree ()
  "Show or hide the current subtree depending on its current
state."
  (interactive)
  (save-excursion
    (allout-back-to-heading)
    (if (allout-hidden-p (point-at-eol))
        (progn
          (allout-show-current-subtree))
      (allout-hide-current-subtree))))