SLI ndi ntchito yothandizira yomwe imachenjeza woyendetsa crane kuti akuyandikira zinthu zambiri zomwe zingayambitse kuwonongeka kwa zipangizo ndi ogwira ntchito.Chipangizocho sichikhala, ndipo sichidzalowa m'malo mwa kuweruza kwabwino kwa wogwiritsa ntchito, chidziwitso ndi kugwiritsa ntchito njira zovomerezeka zogwiritsira ntchito crane.