Reading the scrum guide is not a big thing, adding more theory is also not much effort, you just need some reading time. Are you, after reading tons of literature, a good Scrum Master / Agile Coach / Product Manager whatever? Not at all, you learned the theory – this is not the hard part of the job. Even if you can quote them you are not a hero – you just proved your reading skills. Experience and adaptation are what you really need to grow and this is something nobody can teach you by book … you have to make your own mistakes and go through your own failures to grow. None of these maturity models try to really focus on this. Why? Because it is almost impossible to measure or maybe it is too much common sense.