I read the book over several days then experimented with the knowledge I had gained by upgrading my reusable C++ Finite State Machine classes to add a subset of the most useful heirarchical state machine features.

All the debugging, banging and refitting I did to my classes gave me an appreciation for how much easier it would be to code and maintain statecharts using the author's pre-selected ideas and coherant, maintainable, elegant framework. My legacy design is about 180 degrees from the authors, using state objects (e.g.: I used nouns, and the author uses verbs) and all my functionality is set in externally through event and transition functions. Even using the book from that divergent viewpoint, the book's information and method of presentation was very useful.

On the logic side, I'm reimplementing some standalone FSM algorithms using my new statechart capabilities and I appreciate the grounding in practical statechart design I received from this book. This includes a basic set of the most useful and powerful features and an understanding of how to implement more complicated special purpose features if I should ever decide I need them, and also an understanding of why I may never choose to do so.