If that's the main argument, I don't see why park-adjusted ERA is any worse an indicator of future success than FIP-based ERA. I don't understand. ERA and ERA+ are soley based on how many runners crossed the plate. FIP based ERA is based on everything but that to find out how many runners should have crossed the plate on average. They are completely different stats. That might be the case, but in 6 of his 8 years, his ERA has been better than league average. This has some legs. I'll acknowledge that whatever he is doing is working, because he has kept his ERA consistently below his FIP and well below his xFIP. However, like me and Ennder have been saying, this could be partially because of the Cardinal's stellar defense.