Defensive metrics are better looked at over a larger sample of 3 years, rather than one, to get a good idea of a fielder's true defensive talent. That said, the stats over one year give you a fairly good idea of what a defender did on the field that year. The more stats you look at, the better the overall picture.
Jacko posted the numbers of Didi and Xander for dwar and UZR/150. They aren't as close as you make them out to be. Also, Didi has a DRS of 5 while Xander's is 0. SABR gives Didi an SDI of 3.2 over Xander's 0.1.
The Fielding Bible Awards are out, which I didn't realize. Andrelton Simmons from the NL won, hands down with 120 points. In the AL, Didi was the vote leader with 46 points, followed by Hardy, Escobar, Iglesisias, then Bogaerts, who received 17 points.
You are making me agree with Jacko and defend a Yankee player, which I don't like doing. So quit being a homer and stop.