I always heard it as "i before e, except after c, or with the sound of a or i".
Therefore feisty, foreign, neighbor, receives, eight, counterfeit, beige, sleighs, caffeinated, and weightlifters all FOLLOW the rule. Keith and atheist do not belong on the list because Keith is a proper name and -ist is a separate syllable. Leisurely and weird do, indeed, break the rules.
Class dismissed.