I don't THINK I need to point this out to anyone but I'm gonna say it anyway.
That's about the worst possible way to separate the ball joint and spindle. The guy says, "without damaging anything" except if that ball peen hammer slips one time and hits that threaded shaft and screws those threads ALL to pieces. Even if he doesn't slip, hitting the ball joint "on the side" like that is a surefire way to damage the joint. The joint is designed to take loads up and down, hitting the spindle "backward" like that is loading the ball joint in a way the socket IS NOT designed to take.
I agree with the person in the video that a pickle fork is NOT the right way to remove the ball joint either. The absolute best way to remove a taper shaft ball joint without damaging the boot OR THE JOINT is to use a "press" type ball joint separator.
Sears: Online department store featuring appliances, tools, fitness equipment and more
KD tools #3916 $17.99 at Sears.com and no damage at all to either side of the suspension.