Working the ball" means causing the ball to curve in flight in the desired manner. Some people are saying that a cavity back iron could not 'work' the ball. More than half of the Pros on Tour are using cavity back irons. All pros must be able to intentionally "work" the ball in order to compete. If it really were true that a cavity back could not 'work' the ball, you would see all the pros using muscleback irons. Since that is not the case, this statement is a myth.