I've seen this information here before, maybe by you; maybe by some other poster. For about 40 years, I've followed the published velocities of handgun cartridges, especially those useable in small .38's. (I've been a serious student of guns since I was 12 years old.) Invariably, the Plus P rounds clock faster, except for some 158 grainers. Jacketed bullets in that weight are too slow for .38's.
Typical non-plus P's have often been found to travel no better than 650 FPS, some even slower. The Speer Gold Dot 125 grain +P will give close to 900 FPS from a two -inch gun, and over 950 FPS in a three-inch.
I have a letter from Federal's PR man, whom I asked to check with factory technicians on the speed of their 129grain Hydra-Shok. The lot of ammo they tested ( in revolvers, not pressure barrels) gave 865 FPS in a snub and 936 FPS in a three-inch barrel. This jives quite closely with results posted by writers who have tried this load for magazine articles. Remington's 125 grain +P is also pretty warm, about 890 FPS in a snub. A SHOOTING TIMES article showed it at 950 FPS in an L-framed gun with 2.5 inch barrel. A three-inch would probably get that up to 975 FPS.
Lead HP's usually clock from 750 FPS to about 825 FPS, depending on the brand and lot and the gun used. They may well open up better than JHP's because they have no jacket to rupture.The JHP's tend to penetrate well, getting deep into even a large body, and carry more energy than standard-speed loads. (I don't use .38 ammo with bullets weighing under 125 grains; they may break up or not penetrate enough.)
Marshall, Sanow, Ayoob, and others all show the +P's giving about 66-67% one-shot stops. Standard rounds are about 50% or a little less. Wadcutters appear not to help much, if any.
Sorry, I cannot agree with your post. I respect your right to believe that, but I really think the evidence is clear. Plus P's are the route to go if the gun in question will take them. This is naturally for defense against man or beast. Shooting paper or cans works fine with standard loads, and lets the gun last longer.
Lone Star