A golfer who needs help squaring the clubface or one who has a slower tempo is better served by a shaft with more torque. Conversely, golfers with faster tempos need less torque. The average player benefits from at least two or three degrees of torque. We have some ladies and seniors shafts that have up to six degrees of torque, and they feel good. Slower swing speeds can effectively use higher torque shafts, and faster speeds need lower torque.
Some ladies can use up to five degrees of torque effectively.
Better players need less torque because their swing speeds are generally higher and they have less trouble squaring the clubface. On the whole, however, the most important thing regarding torque is that it's consistent throughout a set of shafts. While that's often true for Tour players, who put a premium on accuracy, I think the average or recreational player should use the most flexible shaft they can hit straight. Softer shafts are more forgiving and make getting the ball airborne easier. Trying to hit shots with an overly stiff shaft isn't easy.