You can do this protocol using dumbbells, a barbell, or on a seated row machine. The isometric is held at the full contraction because it forces you to focus at the top of the row – the part of the exercise where most people cheat.
Also, if you're using free weights you can vary your torso lean from a 45-degree angle to parallel to the floor, thereby hitting your muscles a bit differently.
The Shotgun Method allows you to train for both size and symmetry without having to skimp on either. It actually allows you to concentrate on the big lifts without neglecting isolation exercises that address lagging body parts.