anchor.diff:                                 "C-t" 'make-buffer-focus
                                  "C-m u" 'bookmark-url
                                  "C-b" 'show-bookmarks
  +                               "f1 f1" 'help
  +                               "f1 t" 'tutorial
                                  "f1 v" 'describe-variable
                                  "f1 f" 'describe-function
                                  "f1 c" 'describe-command
  
positive.code:                                "C-m k" 'bookmark-delete
                                 "C-t" 'make-buffer-focus
                                 "C-m u" 'bookmark-url
                                 "C-h v" 'describe-variable
                                 "C-h f" 'describe-function
                                 "C-h c" 'describe-command
  
negative.code:                                "m d" 'bookmark-delete
                                 "C-o" 'load-file
                                 ;; TODO: Use "f1 *" instead?
                                 "C-h C-h" 'help
                                 "C-h h" 'help
                                 "C-h t" 'tutorial
                                 "C-h v" 'describe-variable
                                 "C-h f" 'describe-function
                                 "C-h c" 'describe-command
  