Such an approach yields predictably boring results. The fix requires some unscripted preparation that will pay off in several ways.
What's really lacking in a robo-speech is awareness of the crowd. Successful entertainers tell us that each audience is different, and the presenter should have a sense of the atmospherics in the room and adapt the presentation accordingly. Here's a tip on how to do that from Robert Pozen, a professor at Harvard Business School, who has a popular series on personal productivity on HBR.org.
First, ditch the script and jot down a list of four or five key points and a concluding paragraph. Then show up early enough so that you can talk with audience members and get a sense of what's on their minds, their moods, their expectations. Then tailor your talk to what you learned from your audience.
I like this approach for another reason. Even the most jaded speechmaker has some butterflies before hand. This exercise should help you focus on what you are going to say rather than how nervous you feel.
Ever given the wrong speech to an audience? Did you recover? How do you prepare now?