It's a general theory that people think relievers are better than starters, but it's hard to compare pitchers who pitch one inning and throws 16 pitches compared to a pitcher that pitches 6 and throws 100 pitches. I'm not sure relievers are better, or do throw harder on the whole. A guy who comes in for one inning can throw as hard as he wants because he doesn't have to pace himself for an entire game. I remember watching the All Star game a few years ago and Brad Penny was pitching during his best years with the Dodgers. They guy very rarely broke 94 or 95 during his starts came out in the All Star Game throwing 98-100. Yeah theres a ton of hard throwing relievers, but they wouldn't throw as hard if they had to pitch 6 innings every five days.