I've made it through about 75% of the book and have never gotten the sense that they think everything discussed in the book is something you should always do. Each pattern discussed has a summary of pros and cons. While they may be a bit lacking, they clearly articulate the fact that you should be thinking whether or not the pattern matches the application's needs.

I don't think there's many applications that will require everything in the book but there are certaintly many applications that could apply one or more patterns discussed.