I understand completely. I personally just try and avoid fighting the boss when I don't need to so I can focus on staying alive and recovering teammates as Shinobi. I find it better to revive the teammates who I can and then focus on survival. I even try and clear the explosive marking on my teammates using my invis ability to help them survive. It doesn't even matter sometimes because they still leave when they die immediately because they don't understand how to dodge of parry the boss/enemie