There could be a panel much like the conditional text panel, which allows you to define and name text ranges/sections, which should be stackable.

Thinking of HTML/XML/EPUB export of content, you are then able to feed the sections into div containers (<div class="sec1"><h1>Blabla</h1><p>blablablablabl</p>...</div>).
Nowadays such containers, which you must have according to the DTD/Schema or Website the content will be published after print publishing, have to be added by hand or with tricky XSLT programming.