[drupal-docs] usability of "Avoid all embedded headings"

[Steven Wittens]

A big +1 for using headers inside book pages.

I never understood why this was such a problem or why the rule was added 
in the first place. For the printer friendly version? That one is used 
by a tiny minority of users... the majority sees a page as a single 
XHTML document. Within that document, headers make perfect sense.

Note, I also added some header renumbering page in a book issue to make 
the book pages respect the hierarchy. It renumbers correctly, handles 
missing numbers, and transitions into divs when the h# tags run out...

Steven Wittens