There is more to AA than just the Big Book. Just the second item of choosing not to drink today is one item. When I came in, I didn't have a choice not to drink. Today, the choice to drink is entirely mine to make.
As far as things said in meetings not in the BIg Book, so what? If there was supposed to be an AA Police of what could be said in meetings, I'm sure our founders would of included it in the Traditions.