The idea is what happens to a pedestrian if you hit them. Very often they are taken at or below the waist and the upper body spins and comes down on the hood and/or windshield.
This a bigger deal in Europe than here; the NHTSA only considers it periphally, and it isn't part of the NHTSA crash certification standard. Thus I don't think the insurance companies will make much of it, and I know I won't. Here it is more of a medical community and CDC bray.