they used to say that years ago, but now they say eat to satisfy your appetite.
what they mean is try and make the majority of you meals consist of free foods (particulalry s and ss if you want a big loss).
i eat depending on my appetite each day. some days i'm not very hungry, other days i could eat the contents of the fridge! so on days i'm not hungry i will use this to my advantage by doing success express or eating veg based meals, but on the days i'm ravenous i will fill up on pasta until i feel uncomfortably full, which then stops me wanting chocolate and crisps.