"It's not about the tools." I'm sure you've said that yourself many times. But then where is the underlying thinking explained? Kaizen Express explains super many concepts and techniques, but then goes further. Just one example: each chapter ends with a dialogue between a toolhead and a sensei. Had you already figured them all out? :) In short, a concise, clear description of the elements of Lean in a logical order for both beginners and advanced practitioners.