I think their point was that, sheepherding is a more fulling activity for the dog than whatever human based exercise. i.e. the stimulation a dog gets from shee

I think their point was that, sheepherding is a more fulling activity for the dog than whatever human based exercise. i.e. the stimulation a dog gets from sheepherding outweighs the stimulation it gets from playing fetch and catch with a human.