I have seen the phenomenon (tongue in cheek) on several firearms, all after heavy use. During RO duties at IDPA competitions, I have been lucky enough to see the firearm slide fail to go to battery. On striker fired pistols this has resulted in a light hit to the primer whereas on external hammer ones such as the 1911 the inertia of the hammer strike drives the slide forward sometimes to fire the round, sometimes not.
It's actually rather weird to see as there is a delayed reaction. The truly good shooters are like statues as the round finally fires and proceeds to hit the target where they aimed. The not so good ones, who are fast enough, begin the tap rack drill and 2 of them have let rounds go over the berm. You can also tell the ones who are anticipating the recoil too.
As for the striker fired pistols, I understand their reasoning but I cannot see how the soft primer will overcome the spring tension and slide weight enough to actually push the slide out of battery. Yes, in pure analytical terms of physics that is exactly what a striker fired pistol is doing. Again, it is the disparity of weight and spring tension against the relative softness of the primer that allows the system to work.
