Quote:
Originally Posted by theducks
I believe in K.I.S.S. 
So I set the Title to H1
Any "Parts or Books" as H2
and Chapters always to H3 , regardless of presence/lack of H2.
The TOC will indent properly
Title
Part1
Chapters
Part2
More chapters (those belonging to Part 2)
Partx
. . .
You can still do additional H level styling via the stylesheet |
That's exactly how I do it. It makes sense, after all. Multiple "ultimate" headings is illogical and unnecessarily confusing. What's more important than the title, ie, the book itself? Volumes or Parts are obviously next, followed by Chapters, Sections and Subsections. That leaves you H6 for Sub-Subsections, which are pretty rare.
Use all 6 standard headings properly, and style them to suit yourself. I've only had one book that required more levels of organization. (I used <h6 class="h7"> as my header, but there are probably better solutions.)
Workarounds for individual readers aside, anything else is bad structural markup, in my opinion. And even those workarounds bear the danger of becoming accepted (bad) practice.