From Jon Heyman:
The Yankees argued Wang was a lot closer and really no better than Scott Kazmir, and that Kazmir, along with pitching notables Joe Blanton, Freddy Garcia. Roy Oswalt and John Lackey all got $3.8 million or less. It probably didn't help Wang that he bombed in the playoffs last year, leading to the team's early ouster.
...
Wang's reps emphasized his 19-win total two straight seasons. They also tried went a little nuts in the hearing room when they described him as "the Michael Jordan of Taiwan,'' and actually produced a graphic depicting how the Taiwanese stock market fluctuated on days he pitched.
As the arbitrators ruled: Who cares about that?
I would have looked at innings pitched per game (arguing the value of a rested bullpen). I would have looked at pitches per inning and the time the team spends on the field behind Wang (a pitcher who works quickly helps his team perform). I would have looked at those wins against what other Yankees have been able to do.
I hadn't realized that he was asking for a record amount of money for a first-time arbitration player, and in light of that, the decision seems like a slam dunk for the Yankees.