Well done on your loss! I suppose that I do this to a certain degree, as on the conventional WW plan you can save 4 points a day over the week if you know that you are going out at the weekend etc. I make sure that I do this if I know that I'm going to be eating somewhere where I'm not going to be sure of the exact points (restaurants, other peoples houses etc)

The only thing I would say to people is that you can actually slow your metabolism, and therefore make things harder for yourself, if you eat too little on certain days after overdoing it on others. Even though it might be the same amount of points spread over the week, your body prefers relative consistency in the amount of food you take in each day in order to keep your metabolism firing at a steady rate. Still, if it works for you, then that's great!