ah so is this how Espinosa always has such a high fWAR? The crappiness of other NL 2B?
No. Position influences WAR directly through the position component, which is the same for all 2d basemen. The positional component takes account of the difficulty of fielding the position and what percentage of the full season you play at the position. Playing Catcher for a full season I think is plus 12.5 runs. SS is plus 7.5; 3B, 2d, and CF is plus 2.5 runs, RF and LF is -7.5, 1st is -12.5, and DH is -17.5, IIRC. There is also another adjustment for games played to reflect that WAR is above replacement rather than above average.
Where Danny cleans up this year is that he plays full time, some at short, and he is a terrific fielder according UZR. Add in that now he produces about slightluy above average runs, and he gets a little over 2.2 wins from the position and playing full time, 1.3 from defense, and .5 from offense.
