It is pretty well established that people will do what they think about doing. But it doesn't follow that if you consciously think more about something you will do it. That is, people who think about food all the time get fat, but people who will themselves to think about being thin don't get thin.
That's the difference though. Visualizing "getting thin" is a whole 'nother world from visualizing already being thin and the emotional state you'll be in once that goal is reached.
