You read all the comments, and I think it may even be mentioned in the guide that "understanding the concept and rules of Scrum is easy, however being able to truly understand and practice it is very difficult". Maybe they should have put a couple extra exclamations at the end of the sentence so I actually believed them.
Complete transparency with a client when you a custom dev house is very very difficult.
But one of the unexpected benefits has been that it has actually improved our service and customer interaction. Because we don't do a whole bunch of specing, and requirements gathering upfront etc, I am able to deal with more customers at the same time. So none feel neglected as they get attention and see progress every week.
I agree - understanding it is easy, mastering it is difficult - it requires a lot of time, communication and patience.
A great quote by Lyssa Adkins helped me a lot -
"The joyful and willful pursuit of high performance"
Enjoy trying to get better each sprint, release or project. Know that you will continually get knocked back down. (team member leaving, changing product, hardware fails etc). If you go with this in mind, you should always be content knowing you are pursuing high performance.