If this is true, that is, all or most semi-auto pistols are susceptible to malfunctioning if they are not gripped in a less than ideal manner (and like some others in this thread, I'm not buying that argument because my experience with many semi-auto pistols over the past many years suggests otherwise), then I would never depend on a semi-auto pistol for use in self-defense.
Way too many times for various reasons (to include having slippery hands from blood or sweat and/or having to shoot with the "weak" hand), getting any handgun into play from cover in highly stressed circumstances is going to result in it being grasped in a less than firm grip.