Believe me, they have gotten better. The coaches at Missouri aren't stupid and would have fixed it if they were concerned. and the Nats might too if it bothers them. Didn't work so well for Detwiler though.
I agree that the coaches at Missouri are not stupid, but if anything that is why they would NOT have changed Crow's mechanics. It takes 2-3 years to settle into new mechanics for most guys and as a college coach, why would you tinker with your ace's mechanics to the detriment of your team's win-loss record?