I think guys like Berto, Gamboa, and Dirrell are all faster p4p than Pacquiao or Mayweather at this moment, but the reason these two are the most dynamic is simple.
Manny throws harder combinations faster than anyone else p4p, he can be moving his feet along with throwing combinations which is extremely rare to see, it reminds me of Roy JOnes, but even Roy through hooks in similar situations to where Manny is throwing straight punches which is more difficult.
Floyd is always in balance, and his one punch speed is as fast as anyone's. I just think he is more focused on accuracy and landing solidly than purily outspeed his opponents. Watch him against Marquez and Mosley, his hands are much faster against Mosley because he is a quicker opponent, and Floyd was backing him up. Against MArquez though he was just catching Marquez come in. I think Pacquiao also puts more on his punches which is why his punches would be thrown faster for hte most part, but again with the example of comparing PBF-Mosley to PBF-JMM, it is clear FLoyd was throwing harder against Mosley, and his punches were significantly faster because he was putting more force behind them. Also combinations build speed based on the momentum of the body, and Manny is an amazing combination puncher, whereas even when Floyd puts punches together each punch doesn't carry forward the same sort of momentum, and it almost seems as if Floyd thinks out each punch he throws even in combinations.
All in all I think Manny clearly throws punches in bunches faster than Floyd because, Floyd doesn't really throw punches in bunches, but their handspeed for individual shots is roughly equal.
I also don't believe Floyd's reflexes in terms of physical reflex is superior to Pac's who has shown the ability to counter his opponent impressively, but Floyd has better intuition in there, and because his whole style is geared towards timing moreso than Manny's so he has obviously fine tuned those skills to a greater extent. At the higher levels of boxing its more about experience and what you work on that dictates whether you get hit or not. It's very rare you get guys like Roy Jones jr, but even he had great intuition and you saw in his combinations and the fact he would know where an opponent would be open by the time his punch got there.
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