After I contacted Simon Lancaster, he was gracious enough to respond:
If you look at my own books, particularly Speechwriting: The Expert Guide, you'll find a ton of sources. Warm wishes, Simon
The two resources that most stand out to me so far are Aristotle's Rhetoric and Cicero's Rhetoric ad Herennium, and I plan on tackling them next.
I might mind the qualifications in the review I posted of Lancaster's title as I would situate it somewhat differently from where Lancaster situates himself. My Amazon review presently reads:
★★★★★ Gentlemen's duel? Try assassin's duel!
One part of the filtering in law school filters out some of those who are squeamish about bad argument. The pressure is to pick whatever argument that would best win the case: no argument is too slimy, or would make too disastrous a precedent in the precedent-based field of law, if it will win. That is a lawyer's job, and as best I can tell the idea of holding to solid, honest, argument falls somewhere between being quixotic, and being a category mistake.
This is a book for what will work best at its center of gravity in political and political-like speeches. While the author claims universal jurisdiction, and says of Wesley's work and an Apple product launch, "The principles are identical." (Compare the Dorothy Sayers, The Dogma is the Drama, where Sayers deliberately embraces an unpopular word and argues that the greatest story ever told is positively driven by religious doctrine.) In 90% of the exemplars of good communication are from politics (narrowly construed), and the author does not once countenance the use of solid argument; he compares the use of rational and emotional appeal as a "pea-shooter" versus a "nuclear bomb." Where he references argument, he discusses giving "the illusion of argument" in appropriate places. The dissemination of actual argument is never countenanced.
The book has a genuine place in "philosophy" under an older definition of "philosophy," as do classics like The Art of War and The Prince, but I wince when I see someone in the business world who wants to get serious and deep and reaches for the one or two volume canon of The Art of War and perhaps The Prince. What is called for is wisdom literature, a broad and deep tradition that is older than the books of wisdom literature in the Bible and newer than The Seven Habits of Highly Effective People, of which The Art of War and The Prince represent a dreary sampling for people who want to get ahead in the business world.
This book is a masterful manual of an assassin's duel in the realm of political speeches. For those of us who would like to speak better, it represents all the cards laid on the table for an assassin's duel for how to draw or repel an audience and how to best convince, and there are some cards that a gentleman would draw in argument. This book also represents, more than any other modern text I've read, a meticulous exposition of unclean argument, and it has every relevance to people who want to expose and rebut shady argument (and "illusion of argument"). That is something I searched long for, and failed to find, before going on to write a dissertation on the topic at Cambridge. If I had found this book then, I would have devoured this book and begged the author for more.
I believe that SOME of this book is something I would draw on, but I also believe argument and constructive discourse is possible in communication, including speeches, and the speeches that have most shaped me have involved real and often sound arguments. I believe that this book covers a department of "philosophy," so to speak, and is not the whole, particularly as the author portrays argument as having no place in his jurisdiction. One implication is that his jurisdiction is not universal, particularly not if his jurisdiction does not include any discourse that includes argument.
The work is quite valuable, but it is parochial, and those of us who do not want discourse to always be in the image of political speeches. Speeches can be more varied, and a fortiori lectures can be more varied.
On to what motivated me to buy this book: understanding ancient and modern rhetoric while pursuing discourse that is sometimes not political speechmaking. On those grounds, I would consider this work well worth my money for its references alone.
C.J.S. Hayward, author