Have we all forgotten that it was Paquiao who wouldn't agree to drug testing, not Mayweather? If he agreed to it, the fight would have happened. But to Paquiao, drug testing was the deal breaker. Manny using HGH is the reason that fight didn't happen, not Floyd protecting his undefeated record. For $40 mil, Floyd would risk losing any noght, as long as the check cleared.
Pacquiao agreed to random blood tests up to 3 weeks before the fight, and agreed to any blood tests immediately following the fight.
When he previously gave blood right before a fight, he lost, and he had a superstitious fear that the blood test was at fault.
Mayweather knew this, it was part of the deal that the two teams had negotiated on, but Mayweather played it off like it was Pacquiao refusing testing at all.