I got your Source Code! Books 4 and 5 a couple of months ago. Let me first say that I have played guitar and bass for many years. I have also studied jazz improvisation and music theory in college (not as a major, but for the love of it). Over the years I have learned to apply a lot of the theory to playing chord melody work. But I have to say that your Book 4 has been one of the few books that I have p lurchased over the years that has been life changing with regard to my playing. Believe me when I say that. I have bookshelves of guitar and jazz books. In all of the years, I can point to only three books or series that have been significant in my development. The first was a Mickey Baker book on jazz chords back in the late seventies. The next was a jazz audio tape series by put out by REH with Les Wise. And now yours. I want to personally thank you and commend you on the quality of your teaching and the way you have broken the theoretical into workable, usable tools. It is my firm stand that all complex things must be reduced into simple forms to be usable on the fly. You have done that in spades. I have heard many of these things that you teach in my head for years, but have not been able to get them out to my fingers and my instrument. I am going to recommend your books to everyone that I know. I have already done so with the Jazz Guitar Group at Yahoo.com. There are others in the group who have also used your series. I wish you would consider joining that group. It is free and there are many aspiring players in it who would really benefit from your series. It is my belief that your joining would not only be helpful to many, but a sound business decision.