Although I am a beginner as an author, I have already experienced the wisdom of your advice. Even if you also use someone else to help edit your book, I found it a helpful practice to come back to your manuscript fresh as if you were a member of your target audience can be insightful. Outlining what you have written is also very helpful to help you see if your thoughts are organized well and flow well throughout the book.
Good advice to have the manuscript printed and edited using a red pen. A different experience to read it from a paper point of view vs. looking at a monitor, something I'm used to doing...