I read this book based on Mike Cohn's recommendation. However, I was extremely disappointed in it.
The book starts out telling you what to do to manage Scrum throughout an enterprise. The only problem is the approach given assumes the entire enterprise has embraced using Scrum. I have never seen this. The real problem is typically getting the enterprise to embrace Scrum. The book gives little insight in how to do this. Integrating processes across teams and how to get organizations that work in competition with each other now to cooperate is pretty much ignored.
The rest of the book poses problems and tells you what you need to do, but rarely tells you how to do it. Most often, we are simply told to let the team figure it out. Sort of like a financial analyst telling you - "what you have to do is figure out how to buy stocks when they are low, and then sell them when the stocks go higher." Uh, OK, but _how_ do I do that? The book doesn't quite ever tell us.
The book also tells us about how the core of a system can become dead and tells us we have to stop this. But how? No advice is given on how to write tests or quality code or how to do integration across an Enterprise. In fact, almost nothing about writing code exists in the book. It's as if by following process entirely we can solve all of our problems with code quality, tests, integration, etc ...
My experience with Scrum teams and management is that you must give them reasons to expand Scrum beyond the team or you must explain to them how Scrum can scale when technical problems exist. How do you manage designs across multiple teams? How do you ensure re-use of common modules? How do you manage the dependencies between teams? These are all good questions which go both unasked and unanswered.
I'll admit that I didn't finish the book. After reading about 2/3rds through it I skimmed the rest because it didn't look like any value was coming forward from it.
Two books that I find much more useful are Scaling Software Agility: Best Practices for Large Enterprises by Dean Leffingwell and Agile Software Development in the Large: Diving Into the Deep by Jutta Eckstein