doesnt change the fact they made those real good gains by lifting heavy
You don't like lifting heavy, per your previous posts.
Plus, the point you keep missing is that, EVEN IF you do, the target muscle must do the lion's share of the work.
It's been stated repeatedly that there's a difference between lifting heavy (with the intended muscles getting the bulk of the work) and lifting heavy (nearly every muscle BUT the targeted one, getting the stress).
That's why you have guys who can push 400 or 500 plus, yet have pancake-sized pecs. One example that comes to mind was a pro wrestler from back in the day, the late Ray "Hercules" Hernandez.