Review P: High-level, overview topics for folks who are NOT content engineers to focus on

If you are not someone who spends time developing DTD and RNG, here are the five, high-level topics that your review should focus on: 1.1 Overview of DITA extension facilities 1.2.1 Overview of document-type shells 1.3.1 Overview of specialization 1.4.1 Overview of constraints 1.5.1 Overview of expansion modules These topics need to be as accessible and readable as possible (while, of course, being technically accurate and spec-appropriate).
Here is a screen capture of the review PDF TOC: Best, Kris Kristen James Eberlein Chair, OASIS DITA Technical Committee Owner, Eberlein Consulting LLC 
Skype: kriseberlein; voice: +1 (919) 622-1501