Yes, let's continue to use ERA. I'm evaluating Gibson based on consistent peripherals since May and the results those have yielded: an above average major league starter. And yes, that includes one month where his ERA wasn't sterling. I cited ERA as a stat that helps show his success, but there are others. In fact, I'd argue, many of the best pitching stats for evaluation would show that success if we omitted April. Alas, Fangraphs doesn't allow me to go just from May until now.