Not much is mentioned about happiness. I don't see how there can be enlightenment without happiness. To develop long-term happiness one must be aware of personal barriers standing in your way or preventing happiness in your life. That's the easy part, next acknowledge your barriers and come to terms with your past. Would you rather be enlightened or be happy? You don't have to choose, however, once enlightened there is no turning back. Happiness on the other hand may fluctuate with time. You are better equipped at being happy when you are in the know.