You see even the company pro-shot mis feeds in his vid - this is why people buy auto over pump, along with mag capacity
There is a trick with pump shotguns so they can fire instantly a round is chambered, it also works on auto guns so for the sake of encouraging and informing the wrong people how they can get a full auto etc. so I wont say more but a few of the pro trick shooters do have their pumps modified this way no doubt, they just hold the trigger down and the gun goes bang, bang, bang each time a shell goes in.
Pumps here are so popular here in the UK that if you went into a biggish dealer you might not actually find one on the rack, remember we cannot leave loaded guns by the bed or door to "deal with a problem" as the guy in the video suggests "defensive" guns don't exist in regular households- its a different market without a real defined place for a pump gun