bug#66756: 30.0.50; [PATCH] Improve discussion of 'let' in Elisp Introduction manual

[Drew Adams]

> I think that the lexical/dynamic scope distinction is sufficiently
> important that this manual should explain it, whether or not hiding it
> is simply impossible.
> 
> However, tehre are lots of simple Lisp functions for which lexical
> vs dynamic maks no diffeence.  For example, (defun square (x) (* x x))
> 
> So perhaps it is possible for the first few sections to use examples
> which work the same in lexical mode and dynamic mode, THEN show an
> example for which it does make a difference as a way to explain the
> two modes.

+1.