I'm sad to give this book an "Ok".
The introductory chapters are superb. Allan's clarity of thought and his prose while covering patterns in general, strategy and other concepts is some of the best I've read. It's a pleasure and shows how much energy passion and understand he has.
Thus far it's an amazing book, and really it's worth reading for those sections alone.
The comes the patterns, the diagrams linking patterns are very well made, things are laid out in a clear manner, explanations are good and consistent.
But I had hoped for more than only baseline stuff. The book does a good job of establishing a starting point, a vocabulary for the most common concepts and shows that patterns do work in this context but I found nothing that gave me that deep "aha" moment of seeing clearly articulated and named something that I previously could not name or put my finger on.
My recommendation: Read the first "half" that's truly amazing and dip into the patterns on an as-needed/curious basis.