Technical presenters need to identify what the core message or thesis statement of the presentation is, and repeat it a number of times during the talk. Repetition helps the audience stay focused and to remember the core message at the end. They can become a crutch. It's easy to believe that the technical talk is the visuals. The presenter is always more important than his or her visuals.
Technical talks are about human communication.
That is hard to do when the speaker is reading words and numbers off a screen. The most popular visuals, according to a study reported in Communication Briefings, are handouts. They allow the presenter to rest assured that people will leave the meeting with all the technical detail, but he or she will not have to cover it all from the front of the room. In addition, including copies of the visuals allows people to pay more attention to the presenter and not worry so much about note taking. This allows the presenter to bring up visual data directly from a computer during the presentation.