Keep in mind the $51 million posting fee was a blind bid - they had no idea what anyone else was going to bid, so the Sox had to bid high to make sure they had the exclusive rights to conduct contract negotiations.
Plus, that $51 million isn't applicable to the Luxury tax for the payroll.
There weren't many other options for the Sox for good Starting Pitching out there that wouldn't impact the Luxury Tax they have to pay.
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.