"even a hit in the vest where the energy is distributed to be more like a stiff punch to the chest won't have said momentum to knock somebody over."
Correct. That is also the correct answer to those who claim that energy dump on the target is so important in a SD round/bullet. Uh, a hit to the chest to someone wearing a vest results in 100% energy dump on the target. The bullet is stopped cold. And yet, the person is able to walk away, nothing worse than being winded and bruised, or maybe having a cracked rib. Point: Energy dump means exactly squat. Penetration, Tissue Damage and Shot Placement are what counts. No handgun has enough energy alone to do the job.