I have been on the Yankees board, and for the past several years I have been arguing that the UZR is useless (I did the same thing 11 years ago about the RF/ZR). Sadly, I have watched more journalists trust this stat, and thus report on things that are not happening. I wish one journalist would write a story, please euthanize the UZR stat.
The problem I have with the UZR is that if you plot it among players, and run a regression analysis you will find a minimal correlation to age. Moreover taking some of the best players, the variability within the results from year to year are to put it in layman's terms all over the place.
Last night I made a post on one of the Yankee boards stating how happy I was to see that Jeter's UZR has moved down from costing 50 runs more than the average fielder to 38 runs, I looked this morning and the movement is down to 20 runs. How did one game, specifically the 66th game move Jeter down on an annualized basis 18 runs. Following the logic of this Jeter should have about a dozen ESPN fielding gems. Look I watched the game, Jeter made one great play, but come on already.
Moreover, I was looking at Granderson, according to the UZR he will cost the Yankees about 35 runs more than the average CF. By contrast, Raul Ibanez is actually a plus fielder (he was - 20 last year with Philly)...so tell me if UZR is so accurate why isn't Granderson being pulled rather than Ibanez for better defense. The answer of course is that Girardi isn't an idiot.
I encourage anyone interested in this to pull the best players at respective positions and plot their results, then run a regression analysis. What you are going to find out is that the UZR is meaningless.