>
> Thanks.  I actually had in mind an even shorter variant:
>
>   The @code{(fn)} feature is typically used in the following situations:
>
>   @itemize @minus
>   @item To spell out arguments and their purposes in a macro or a
>   function.  Example:
>
>   @example
>   (defmacro lambda (&rest cdr)
>     "@dots{}
>   \(fn ARGS [DOCSTRING] [INTERACTIVE] BODY)"@dots{})
>   @end example
>
>   @item To provide a more detailed description and names of arguments.
>   Example:
>
>   @example
>   (defmacro macroexp--accumulate (var+list &rest body)
>     "@dots{}
>   \(fn (VAR LIST) BODY@dots{})"
>     (declare (indent 1))
>     (let ((var (car var+list))
> 	  (list (cadr var+list))
>   @dots{})))
>   @end example
>
>   @item To better explain the purpose of a @code{defalias}.  Example:
>
>   @example
>   (defalias 'abbrev-get 'get
>     "@dots{}
>   \(fn ABBREV PROP)")
>   @end example
>
> WDYT?
>

Agree this is a more readable version of my initial attempts.

The only thing that is not clear in my mind is the use of the @ifnottex.
I have left it in the attached patch, as I understand we are trying to
reduce the size of the printed manual?

I have a 2-volume Elisp manual, which is out of date as the current ones
don't seem to be printed.

I have also added a line to the commit message which seems appropriate
here given the rewrites:
Co-authored-by: Eli Zaretskii <eliz@gnu.org>

If this is all suitable to install I agree to close the original bug.