I bought the previous version of this book to help me write a business plan before seeking startup funding for a technology idea. For my needs, this book continues to be my primary reference when writing business plans.
The language used is clear, and there are a few dry jokes that I'm ashamed to say did make me laugh out loud. Having said this, the book is probably more thorough than some readers need - if you want to write the type of business plan that the bank invites you to do when opening an account (e.g. competitive landscape is a single page of local competitors, their prices and their strengths/weaknesses) then you'll find that this book is overkill. If you plan to spend two weeks or more writing your business plan then this book will probably make the process much easier, and lead to a more thoughtful document that stands up to detailed financial and strategic analysis by bank managers, investors, advisors etc. If this is what you're trying to write, then you'd be a total monkey to start without reading this book.