With the cocktail of hormones and steroids that he was taking, he essentially reversed or stopped the aging process. He was a HOF caliber player before his head started growing. He cheated age and the inevitable decline that comes with it. He had the advantage of playing with 15+ years of experience, but with the physical skills of a 25 year old player. Take any retired ballplayer with the benefit of all his experience and put him back in his 25 year old body and he'll perform better than he did when he was 25. What I found amazing was that while Bonds was on his Roids fueled run, he almost never went after a pitch outside of the strike zone. His pitch recognition was phenomenal, far better than when he was a young player. When he was young, the slider in the dirt was how you got him out. I have heard theories that the Roids improve vision thus helping his pitch recognition, but I have to think that 15+ years of experience had something to do with it.