Bottom line: Pacquiao, realistically, should never have fought above 135 lbs. It is outrageous to hold it against him, Mayweather, Berto, or any other welterweight for not fighting two weight classes higher vs. Martinez. As for JMM III, I believe Pacquiao doesn't want the fight if he is saying things like "people would rather see Mosley". He hasn't forgotten what JMM put him through. Those are the 5th and 6th toughest fights of Pacquiao's career (the others being his three losses and other draw).
In order of what I underlined: Pacquiao's two biggest wins (in terms of vaulting his popularity) were against guys Mayweather had fought and defeated a full 18 months before Pacquiao dared to lay leather on them. Well then, what the hell was Morales II, Morales III, Barrera II, de la Hoya, Hatton, Clottey, and Margarito? I would not, but many people would throw Cotto in there too after his crushing loss to "plaster glove boy" and his straight up bad showing against "punching bag". My conclusion: You are a hypocrite. A big one.