Re: Help menu (was: Re: describe-bindings: ^L, bad order, naming)

[Richard M. Stallman]

        type a key sequence (e.g. `C-M-s')
        choose a menu item (e.g. [menu-bar files open-file])
        click on a scroll bar
        click on the mode line
        click in the minibuffer
        click on an Emacs-related name in a buffer: apropos is called
        click anywhere else in a buffer: its modes are described

It sounds like this does everything that C-x k does
except in the case of clicking on the buffer contents.
Is that right?

     Help is generally provided using `describe-key' and the Emacs online
     manual (via `Info-goto-emacs-key-command-node').  If no entry is found
     in the index of the Emacs manual, then the manual is searched from the
     beginning for literal occurrences of KEY.

I don't quite understand.  How does it decide which one of these to do?
Does it always try each of them?