We may be attending to a specific muscle/s via a certain exercise. However to make an exercise effective; all the muscles – prime mover, stabilizer, synergists etc. have to work equally effectively.
Only when the entire chain works effortlessly that one can squeeze maximum power in a movement and make it energy efficient.
Looking at the video can somebody tell if I am pulling down 80% of my 1RM ? It is this effortlessness that we should seek in training for our sporting movement.
Make movements powerful and energy efficient.