This all boils down to a rule I have for myself whenever addressing a large audience: start by stating the obvious. This does two things. First, it gives peopl

This all boils down to a rule I have for myself whenever addressing a large audience: start by stating the obvious. This does two things. First, it gives people an easy mental on-ramp to follow the thread of what you are saying. And second, it forces you to back way up and cover the ground that is so central to your world you would probably forget to say it, even though it is completely unknown to most of your audience.