The pros and cons stated are all, of course, valid. We all have the experience. Further to this, I generally prepare a PowerPoint show and let it run while everyone is waiting for the session to begin. The content is directly related to the agenda that had been sent out. It occupies the audience whether they're in the session or remote via Webinar. The PPS stops when the session begins, sans PowerPoint. The PPS is sent to the attendees after the meeting, updated with any additional points made during the meeting/training.