I guess maybe I don't agree with most people about this tutorial. I actually think it could use a lot of improvement.
It seems that almost every part starts with a section with all kinds of refactoring. Unfortunately, no code is shown. So each lesson, you have to download new sample code and figure things out for yourself.
It's just frustrating to go through a lesson and write code only to find out that you're just going to replace it. I started reading this because I wanted to write code, not examine and edit somebody else's code.