This is the big one here.
Having Cole Hamels on the Yankees would block them from being able to bring up and have right-hander Dellin Betances and left-hander Manny Banuelos on the roster and in the starting rotation.
The Yankees already have CC Sabathia, Phil Hughes and Ivan Nova as their long-term solutions.
Andy Pettitte and Hiroki Kuroda are on one-year deals with the Yankees in 2012, but probably wouldn't figure into the long-term plans of the team.
The Yankees eventually would like to bring up both of their top prospects in Betances and Banuelos, known as the "Killer B's" in the minors.
If the Yankees sign Hamels, it blocks at least one of them from a rotation spot.
What good would the the Yankees have done by trying to develop both of the youngsters and then not have a spot ready for one of them?
It ends up being counterproductive and goes against the principle of developing a young player.
The Yankees used to make those mistakes and ended up trading away their farm system not too long ago. Yankees GM Brian Cashman has worked very hard to rebuild it.
Having Hamels on the Yankees would do more damage than good.
In the end, Cole Hamels is just not worth the hassle of having in the Bronx.