This can't be repeated too often. It's the reason my normal daily carry piece is a 3inch 5-shot 44 Special with either 200gr WW Silvertip hollow-points,or handloads with wadcutters. The ONLY place I disagree with the quoted study is that a large diameter bullet at even moderate velocity can penetrate deep enough and still have enough "mass" to break a spine,ending the assault on you. This is just nitpicking,though. The head is a MUCH easier target to hit than the spine.
BTW,don't waste your time trying to give me grief about the handloads because some rent-a-cop preaches against them. I've heard and read all the arguements,and concluded I know more than he does. If you don't like that,tell it to somebody who cares,and be happy following his advise. I'm not trying to sell you any books or videos,and I don't care.