In the IX marks journal there is a largely positive review of David Murray's How sermons work. I enjoyed the book (five of your English pounds well spent), but there were one or two places where I did not agree entirely with the point being made. I notice that Aaron Menikoff (the IX Marks reviewer) thinks the same:

Is it true that the preachers deemed most “authentic” shy away from sermon notes? I don’t think so. Yet Murray warns preachers not to use exhaustive manuscripts since “this age prefers to be spoken to personally and relationally. There is nothing more authentic than a man preaching eyeball to eyeball, heart to heart, without anything intervening” (149). This is a small point and it’s hardly crucial to Murray’s task. Still, it is a point I hear regularly, and I’m not sure it is accurate. Authenticity in preaching does not stem from the use or lack of notes, but from a preacher so engaged in the Word, so convinced of its relevance for today, so gripped himself by the power of the gospel, that his conviction is powerfully and spiritually evident—notes or no notes.