Master Pages, ToC, reapplied synch, section headers
The behavior of master pages does not do what is intended and there are several questions that needs to be answered.
The master pages have two boxes for filename (ie chapter name), a second box for section header that will be overridden in a normal page later. See image below.
The chapter numeral has been unticked as: "Allow Master Item Overrides", because the chapter numeral is based on file name, which won't need editing.

Then after changing the master, synchronizing the book, InDesign ends up with this:
Reapplied master objects, chapter object ignored by toc.

TOC goes from this, to that ->

So here's a couple of questions:
What exactly is supposed to be on a Master page?
Is Master pages not supposed to be a template?
Why are overridden objects from a Master page reapplied?
What is the purpose of having master pages with "LOREM IPSUM" dummy objects if they will just be reapplied under the overridden objects?
What is the purpose of having chapter numerals as dummy objects if they are not included by ToC?
Picture below shows the most common problem on the left, and the ideal situation on the right, but the ToC doesn't include non-overridden objects.
What is the solution?

