I'd give this impressive book an "MBA" rating - for Meticulous Business Audiences only.
Its contents are broad and deep enough to address the requirements of any-length plan, be it a 20-40 pager for a small and straightforward business or a "beauty parade" document of over 500 pages.
The chapters, collectively, are well organized according to the stages of the planning process and because each one explains the fundamental concepts associated with each stage, it sort of seems, when you're reading, like you're on an MBA-curriculum tour. I was reminded of The Ten-Day MBA by Steven A. Silbiger; however, this is closer to a traditional textbook. It's also *loaded* with relevant business planning tools and techniques that range from simple to sophisticated, and from qualitative to quantitative.
I don't see this only as a guide for preparing a document (i.e., the plan). It's not just for one-time use. In a bigger sense, I see it as a manual for drafting a blueprint for success - which is a year `round endeavor. That's what ultimately compelled me to *buy* the book after having first borrowed it from the library.