I sense collusion between Oscar and the coach who made this youtube video. I think this guy is helping him out and bringing an international flavor to the issue.
More than Oscar, I question the motivations of this guy. Why? Isn't it just a highly pious sounding video (this is all meant to help you understand how to serve) made with material which should not have been accepted in the first place? A whole lot of deception here. I don't trust this guy at all.