In my limited real-world experience humanoids struck by .38 s&w special wadcutters and semi-wadcutters ceased being threats upon being hit. I fail to understand why some threats would continue to be threats if hit by accurate fire from a .38 s&w special. Of course as the .357 remington magnum and .38 s&w special +p are 'faster' .38 specials they would also do the job, certainly no worse, maybe better, (I mean how much dead-er than dead can one be.) I also fail to understand how a humanoid hit with inaccurate fire (say in the glute or thumb) by a .357 would be more incapacitated than if hit by inaccurate fire from a .38+p or garden variety .38. Being more powerful I am certain the humanoid hit would sustain a greater amount of tissue damage, but I don't see how that translates into incapacitation with periphreal hits or how the greater energy transfer is meaningful in cns or cartio hits.
As a disclaimer I might add that with all due repect I think Dr. Roberts is doing a phenomenal job of measuring with great precision (I am sorry, here) the wrong variable. In my limited real-world experience hollow points fired from snubbies don't expand. Flat lead metplats crush and destroy tissue. Velocity is not as important as momentum. Expansion is irrelevant, the amount of tissue disrupted is significant. The placement of a projectile is paramount and no amount of expansion can correct poor placement. (Just my $0.02)

__________________
Certified Curmudgeon