The guy's a business man. I don't know about any other business men here, but when I am with my team, we chat about things and then brainstorm ideas. He's brainstorming ideas, whether they are possible or not, that would be for the doctors and scientists to determine.
When you are the president you don't brainstorm dumb ideas during a daily press conference that is being watched around the world...
And as a businessman he should know better, since a CEO would be a total idiot to brainstorm ideas during any public event, as well.