It is critically important that you get your client customer colleague, really comfortable with a great message. Because the reality is you can look great, comfortable, confident, relaxed. You can be speaking lots of sound bites, you can make the report and like you. If you don't have good solid messages, nothing else matters. Ultimately it is about communicating important messages about your organization. So, I look at it as the fundamental building block of the whole interview.
You don't have that you don't have a strong foundation. It all crumbles. So, look at it, look at it again, redo it, tweak it, keep doing it until you and your colleagues are completely comfortable with the message.