The cable Pullover offers up resistance all through the ROM and the lats have the best leverage through this joint angle ROM, this is how you train the lats (secondary triceps) with a pullover (same with the pullover machine set up). On Cross bench pullover, there is around 160-180° of flexion, this is where the pecs and triceps have the best leverage to do shoulder extension. On top of that, since it’s a dumbbell then the peak forces are also there at the top, so this is (mainly) a costal pec e