The Stephen R. Covey engine has kicked out numerous books on self-help, and they consult 200 out of the top 500 Fortune companies. After all of those books and years, they have heard enough stories and waded through enough crisis situations to get a good handle on what works and does not work in all of those environments.
Now, if you've read every book they're written, then undoubtedly you're going to begin this book and say "I've read this all before". Naturally, when they begin a book, they have to assume that some readers haven't read the other books yet. They have to catch them up on the background and basics. If you don't need that primer, then skim for a while. It's not a bad thing, it's a normal thing. It's how book writing works :) If you pick up book 5 of Harry Potter, you still have to go through a little bit of scene setting for the .00002% of the population who skipped the other books and lept into Book 5.
So now, onto the key points of this specific book. Time management is good. Organizing your goals is good. But all of these things are only good if your goals are actually valid ones. If you spend all your time creating to-do lists, and carefully plotting out weekly goals ... but your goal is to get a "bigger fur coat" while your children are starving and you're miserable at work, something is out of sync. This book is all about making sure that what you do is what you REALLY want to do. It's about a higher level of time management.
So they're not saying the other time management systems are bad. They explicitly say that each has its place in life! However, if you work very hard every day to climb a ladder, and find after many years that the ladder you've climbed was against the wrong wall, then you'll be very disappointed. You should always make sure you are working for a goal that you really feel is important at a basic moral level.
This isn't a book to just plow through in an hour and see what you remember. It's asking you to really think about why you do things in life. Is it because your parents harassed you when you were young, and you want to get a flashy car to prove you're something? Do you try to out-do your co-workers even if it hurts your home life? Sometimes these answers don't come easily. If they did, I imagine we wouldn't need a book to help us sort them out.
This is a good book to read a chapter, then put down for a while. Go back and read another one, then think about it for a while. The basic concept is easy enough to understand. Divide your tasks up based on what category they fall into -
Quadrant I - urgent, important
Quadrant II - not urgent, important
Quadrant III - urgent, not important
Quadrant IV - not urgent, not important
Sounds easy, yes? But how many of us get sucked into a ton of "urgent" but really not important tasks for all sorts of reasons? It's the planning - the Quadrant II time - that can help fix those issues. But we have to make time to plan. If your life is full of incessant urgent demands, it may seem impossible to do this. But it can be done.
A hard idea to wrap your mind around is that we all only have 24 hrs a day. Leonardo Da Vinci, Ghandi, every one of us has 24 hrs. You might say "Well but I have 3 kids at home". True! So in your life, you made children your priority. You wanted those kids! So embrace that, and accept that as your mission. Put aside other less important things. We all make choices in life about what is important to us. When we make those choices, we should accept that, be happy with that, and find ways to emphasize our time in those areas. You have to choose to spend the time on things you love - not to divide your time up amongst various things that are "OK". That's what the main lesson is here. Focus on what is most important - don't try to do 80 quadrillion things that are all "OK". It can't work.