If you decide to give this book a read, be sure to access a newer edition even if it is to read the authors updated notes. I was not a huge fan of this book and very much agree with the authors statements of improvements he would like to make to the original. I felt this book contained many circular arguements and at point really stretched the readers vocabulary. This is one of those textbooks you sell, but thats just my opinion, there are numerous other students who really find this book incredibly useful. Unfortunately I am not one of them.
This is a great read. It is hard to believe that it is as old as it is (even the revised version with a new preface). I found it a wonderful tool for engaging in and developing a preaching style that is accessible and beneficial for congregations. The author has some wonderful insight and selects quite a few (mostly Lutheran) theologians to support his suppositions. Well worth the library for ministry.
I'm Lutheran-partial anymore, but can't think of much reason any theology student, Lutheran or otherwise, considering taking on a career in preaching (or in just theologizing) shouldn't read this short volume.