I'm not sure what pictures you are referring to, but the "normal" rig which permits control from either seat provides only a 2:1 advantage, and you will therefore see only 2 lines running from the clew to the rear of the hull. In order to get a 3:1 advantage, you need 3 lines. In either case, the person in the back seat gets to know them very well when tacking or jibing. Just be sure that you have a keeper strap on your sunglasses or you will have my son's experience, where the mainsheet snagged his Oakleys from behind and tossed them into the bay.