As a public-speaking reference, this is fairly solid: a quick read that gets right to the point, no fluff or wasted words (plus chapter summaries and a tips reference list at the end). However, this also means concepts are simplified and expressed in absolutes, and there's some repetition where some of the 23 tips could be easily combined or are just the same idea framed differently.

Worse, there's a lack of human empathy which leads to a TED Talk about domestic abuse being distilled to "Look at this powerful example of [narrative] conflict" and to an in-depth discussion of the graphic details of sheep castration.