Here's how you know if someone is living the brand, is emotionally connected to the story and is literate and informed–or if they're just emotionally connected in the moment:
Ask a lot of questions.
Cornel West can talk for hours about race, the Bible or Marx. He knows it cold.
Dan Dennett can write for three hundred pages about the philosophy of free will and consciousness and he's just getting started. There's depth there.
I've talked to brand stewards from JetBlue and Starbucks that could go deep or wide or detailed for hours.
Then compare these passionate leaders to a pundit, spin doctor or troll (for just about any cause du jour) being interviewed on TV. After three sentences, they run out of assertions, facts or interesting things to say.
There's a lot to be said for being deep, scientific and informed.