LOL you are trying to throw s*** to wall expecting some stick. It won't happen mate. A 4.65 & 5.52 ERA are horrible ERAs. It represents 50% of his tenure under that contract. Also a 4.28 is an ERA of a No. 4 pitcher. Mediocre.
If you want to pay 20 M/Y for those ERAs, be my guest, but nobody would, even in today's market. His contract was a mistake from day 1.
Now, If you add his 2015 numbers, his tenure in Boston is lamentable.
.... and if you add his final days with the NYM, you just confirm the kind of pitcher he was. HORRIBLE.