Not impressed by Jose Luis Castillo in 09?

Manny Pacquiao has Castillo as a sparring partner and is "dominating" him. This question isn't to belittle Castillo but to question the point of Manny's people putting out there that he is dominating a former champ, who hasn't held a title since his 4th round KO loss to Ricky Hatton. RICKY HATTON! So this is suppose to mean something? What does it mean (if anything)?