Dear JoAnn,
I agree with your post completely! If only we could transplant these thoughts directly into the brains of leaders.
 I can contribute that another way to keep people in the moment is through mindfulness when speaking. I tell clients that they need to stay "in their sentence" until the very end, to the period. This way they stay focused on their comments, rather than racing ahead to what they want to say next. This focus reads as caring and attention to their audience, and that is the best message you can send!