Perhaps 'chapter' is a bad choice of term
thereby. But if you wrap
entire chapters in DIVs, you may need to physically break a div in the
middle when you paginate.
How you split something into pages is a matter of layout, not content.
The div tag is part of the content. How you show the contents of that
div tag is another matter entirely. If you are talking about a
webpage, then there is no need to split it at arbitrary points (since
there is no absolute limit on length), so you should always split at a
logical break (perhaps a subsection of a chapter, but that should
still be determined with divs), if at all. You have to remember not to
think of wiki articles as webpages - they can be displayed in any
medium imaginable. If someone is printing them in a book, they will
worry about were to put the page breaks based on the logical structure
you give the article (primarily using headers, and using divs
explicitly for more complicated things).