structured paragraphs, paragraphs with indented sub paragraphs

[Marshall Schor <msa@schor.com>]

Many times in my technical writing, I want a subordinate thought 
expressed as a sub-paragraph.

I've tried using <longquote> - that's OK but it also indents the right 
margin - I only want the left margin indented.

I've tried using <itemizedlist> - that works if I use an undocumented 
"mark" attribute to turn off the bullet. 
  (Looking at docbook 1.72.0 I found you can set the "mark" attribute to 
"none")

The best would be to allow <para> to have nested <para> elements, with 
the semantics of the nested ones would be indented
relative to their (immediately) containing <para> nodes.  This has less 
"tag" overhead (meaning, the number
of elements / attributes needed to specify) than the other two 
approaches above.  Has this been considered?

-Marshall