You don't want to make fore/aft adjustments by moving the saddle because it'll affect the position of your saddle relative to your crankset. In general, I subscribe to the notion of positioning the saddle relative to the crankset and then positioning the handlebar in relation to the saddle. That way, you can adjust saddle-to-crankset and saddle-to-handlebar relationships independently of one another to get both dialed in precisely how you want them.