Difference in Team ERA and Team DERA

So, for those of you who are unaware of what dERA (Defense-Independent ERA), here's a brief definition from Wikipedia:

Defense-Independent ERA (dERA), created by Voros McCracken, projects what a pitcher's earned run average (ERA) would have been, if not for the effects of defense and luck on the actual games in which he pitched.

I think that's pretty point blank. Just go show you which variables are used to determine it, they are: batters faced, home runs allowed, total walks allowed, intentional walks allowed, strikeouts and hit batsmen.

And my point here today is to differentiate between those teams which have most benefited from their defense (ie: have a negative difference between ERA and dERA) and those who have been most hurt. In a round-a-bout way, it's determining who has the best defense without taking into consideration hollow stats like fielding percentage, errors and such.

Onto the numbers...

Most Helped by Defense

Rank	Team	ERA	dERA	DIFF
(1)	Phillies	3.93	4.26	- 0.33
(2)	Athletics	3.73	3.96	- 0.26
(3)	Angels	3.88	4.09	- 0.21
(4)	Rays	3.77	3.95	- 0.18
(5)	Cubs	3.82	4.00	- 0.18
(6)	Brewers	4.00	4.16	- 0.16
(7)	Red Sox	3.77	3.91	- 0.14
(8)	Orioles	4.67	4.80	- 0.13
(9)	Cardinals	4.24	4.36	-0.12
(10)	Mets	4.07	4.16	- 0.09
(11)	Blue Jays	3.67	3.73	- 0.06

Most Hurt by Defense

Rank	Team	ERA	dERA	DIFF
(1)	Rockies	4.82	4.19	+ 0.63
(2)	Rangers	5.31	4.74	+ 0.57
(3)	Royals	4.62	4.05	+ 0.57
(4)	Pirates	5.18	4.69	+ 0.49
(5)	Yankees	4.27	3.84	+ 0.43
(6)	Reds	4.58	4.23	+ 0.35
(7)	Diamondbacks	3.99	3.64	+ 0.35
(8)	Giants	4.27	3.97	+ 0.30
(9)	Mariners	4.42	4.13	+ 0.29
(10)	Padres	4.32	4.05	+ 0.27
(11)	Twins	4.33	4.11	+ 0.22
(12)	Indians	4.40	4.20	+ 0.20
(13)	White Sox	3.99	3.82	+ 0.17
(14)	Marlins	4.52	4.36	+ 0.16
(15)	Dodgers	3.66	3.57	+ 0.09
(16)	Nationals	4.42	4.34	+ 0.08
(17)	Astros	4.58	4.55	+ 0.03
(18)	Tigers	4.52	4.50	+ 0.02
(19)	Braves	4.06	4.05	+ 0.01