Oh Roisin what the hell is happening with your brain? There´s a lot of similarities into The Fashion Industry, GaGa is not the only one using "your style".
I like GaGa. Maybe not to much as a person, but her music is very good. However, when it comes to fashion I do think that she adopts some styles used in the past and makes it look like her own. I don't think GaGa "stole" the style, just probably got the idea and tried to come up with a similar look.
