In my opinion, this chapter expands the concept of UbD planning to the broader sphere of entire curricula and programs. As the authors point out, the logical order in which one might lay out a summary of the knowledge in a given field is not usually the best order in which to present that material to a beginner.
I found this chapter to be a lot harder to get through than most of the previous chapters. The authors have already made their central points in the earlier portions of the book. They devote their attention to "scope and sequence" curriculum planning without ever defining it; and most of the ideas presented in the chapter have clearly been addressed earlier in the book.
After reading the assigned chapters, I am not sure if this kind of design would be suitable for my context.