you could also avoid using a style-name the is a standard splitting filter
change the stylesheet and usage from .chapter (class="chapter", to something that the splitter won't grab upon.
style-sheet: .mychapt
usage: class="mychapt"
But changing the original (in red)p to h2 should have done the trick so for BOTH the TOC and inline_toc
Code:
<body>
<div class="chapter" id="ch11">
<p class="chapterTitle"><a href="../Text/contents.html#ch_11">Chapter 11</a></p>
</div>