As you have often seen on westside tapes over the years the emphasis is on a extra wide stance in squatting and it works for them in competition, but they advocate wearing groove briefs or a squat suit to save the hips from being beaten up from the stress that is placed on them using this style, it is a cost benefit relationship, in reference to the use of a sumo stance in pulling, Hatfield has stated that those lifters who are stronger in the legs would favour this style over a traditional deadlift, cheers, ashley