You'd like to think that a player won't do that but, far too often, they do. Two things you can almost book: 1. Great year in the last season of a contract 2. Poor season after the big deal is signed. There are obvious exceptions, Texiera started poorly but ultimately met or exceeded his career averages, but there seems to be few of them.
If you can't grow hair on your head, you may as well grow it above your lip.