Many people seem to believe that it is important to fit as much of the content of a conference paper into the conference talk as possible. In order to do so, they speakveryfast. This is rather like believing that the purpose of a movie trailer is to show as much of the movie as possible, and so running the trailer at double speed.
The dirty little secret is that no one in the audience is likely to remember more than the key idea of your talk a week after the conference (or perhaps even an hour after the talk), and if you try to fit too much in, they may miss that key idea. Be honest now, what do recall of the third talk in the fifth session that you attended at your last conference? However, if you get that key idea across effectively enough, your audience just might be motivated to go and read your paper.
People who speed up their talks to fit more in, and use very small fonts to squeeze as much as possible onto each slide, generally are too busy preparing all that material to stop and time their talk before presenting it. As a result they express surprise and bewilderment on the day when told that they have only 2 minutes left, with 20 slides — oh my gosh, my most important slides — left to go. At this point they begin speaking very fast. And when told that their time is up, since they are still not through their slides, they feel impelled to keep on going. At the very least they must present their conclusion. After all, the audience has to hear this.
The members of the audience, who gave up chasing after the speaker and squinting at the slides about 90 seconds in to the talk, but who have been waiting politely to clap at the end, upon realizing that the talk isn’t going to end, are likely to be so busy swearing under their breath that the speaker could give away the secret of life at that point and it would not be noticed.
So remember, less is more. If you can just convince your audience that your paper is worth reading, your talk will have been a great success.