See Greg Maddox vs. Pedro Martinez. Two of the greatest pitchers of all time. Pedro had a few years that are possibly, if not probably, the best three years, maybe four, that a pitcher's ever had. Maddox was a command guy who could stay at about the low 90's, and topped out at about 91. He aged much better than Pedro did, he was completely dominant through the 90's and early 2000's. Power pitching erodes faster than finesse, command pitching.