I'm not an expert, but I will admit I thought all entries in the ePub should be within a tagged section.
For instance I see that the text within Section 2.2 of the second ePub is unadorned. I see
Code:
<h2 id="sigil_toc_id_2">Section 2.2</h2>
<div>
Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? Test of this section: are you able to jump here by tapping on the TOC? <br/>
</div>
<h3 id="sigil_toc_id_3">Subsection 2.2.1</h3>
Surely this explains the weirdness of the inserted spans.