You are right. The diagrams are used as explanations not as the source of the program. But wouldn't it be neat if when you sketch out the state transition in a diagram (how I think about the state transitions), _that diagram_ was the source of truth for the program?
That is the implied point: let's go to places where we already draw diagrams and check if we can elevate them into the program
That is the implied point: let's go to places where we already draw diagrams and check if we can elevate them into the program