Subtleties in communication with ultra-high new worth clients

I work with clients who have $10 million and up in assets. My boss keeps having to deal with upset clients because other reps are missing things in communcation even though at our level everyone considers themselves a master communicator. She wants me to do a presentation on communication to my colleagues but I need help. Will likely need to speak with you to explain examples so you can understand what I am talking about. It is an hour long presentation so I am thinking about 20-25 slide. I have started it but it may be too basic for people at this level. Needs to have expert tips for people who think they are already great at communication and picking up on subtleties before things go wrong.