How? It doesn't do anything to make a powerlifter stronger on his 1 rep max and it doesn't build anymore muscle for a bodybuilder than conventional training. All this does is increase the chance of serious injury.
Please understand I’m not attacking you …
Wrong and wrong.
For the powerlifter, pushed rep/volume sets can very much improve tensile strength in supporting structures, dramatically improve trunk stability and toughen knee mechanics. Also, there is major psychological benefits, as well. And “capacity” betterment will serve its weight in gold come a peaking period.
For a bodybuilder, striving into uncharted time-under-tension/stress in the squat exercise with a heavy (relative) poundage adds MOUNTAINS of lean tissue, everywhere. This concept has been spoken about, by experts, to death, over the decades. And a great many champions will attest to this. Platz among them. For me, my muscular bodyweight has ALWAYS increased as a result of several weeks of concentrated effort to increase accumulated repetitions (well beyond standard 8, 10, 12 tradition) on a singular work set/session. My poundage for this has almost always been 315, 365 and 405.