Well, Pacquiao went up from 130 to 144 or so in what, 2 years? That and he stayed looking ripped and his power still looked good. Personally I think it can be explained (he was weighing 144 on fight night for the JMM fight at 130 and he weighed 148 the night of the Hatton fight, he's just not cutting as much) but combine that with the refusal to take the tests that could really show if he's using or not and of course people are skeptical.