Well, I'm not sure, given the etymology of "tea-bagger" (this is a family blog so don't ask me if you don't know) that I agree with the tactic portrayed in the video, but I guess one way to defuse an insult is to co-opt the term. This is what police back in the sixties did with the pejorative "pig," and what homosexuals have done with "gay" and "queer," so I guess the thinking is that it's one way to blunt some of the derision directed at the tea-party movement:
Personally, I'd rather they not go this route. The more their opponents refer to them as "tea-baggers" the sleazier their opponents appear in the public eye. The epithet does more to diminish and discredit the people who use it than it does the people at whom it's directed.
HT: Hot AirRLC