Conecting the shield at one end only is a valid concept. I just think that the manufacturers are making it seem more than it really is. If they would just say what it is really for, isolating components, then the arrows would make more sense. Implying that cables are inherently "directional" to electron flow is just lying.
Charlie, yes, ground loops too. This connection behaves differently in balanced and unbalanced circuits - ground loops are still possible in unbalanced circuits since the ground must sill be connected between components.