That being said, even I do not completely adhere to every rule given in this book. However, I do take note of them, and follow most of them most of the time. There are certain elements which I follow to the letter, such as the extra comma when separating 3 or more terms with a single conjunction (such as this, that, and another thing).
I recommend that anyone involved with the publishing industry (writers, editors, proofreaders, etc...) get a copy of this book and read it. Even if you don't follow all of the style elements, you should at least be aware of them, and recognize the value of traditional composition.