hes turned into a parody of himself
All that fucking shouting is simply not needed, the guy on the leg extension in the third vid could have ended up with a slipped disc in his back fucking about like that, and all those stupid jerk reps are just a waste of time.
Keep your body still and grind out the reps through the legs slowly and concentrate on what you are doing, you would have hit failure in 50 of 60 reps less than he did