I love it when you folks talk numbers.
The Hockey Analysis site has its own rating system based on goals rather than looking at Corsi or Fenwick numbers (although it also has those numbers posted). The rating system looks at how the player is doing compared to the league average, which to me is a more readily grasped concept.
When you look at how the defence is doing this year overall compared to the last couple of years for 5v5, Edler is not contributing quite as much to goals for, but he is having a bad year for him on the defensive side of the game, and statistically you certainly can argue that he has on average been almost as bad as Rome in 5v5 situations (and yes these numbers do take into account zone starts, and which players including goalies you are playing with and against). Why Edler would have been picked as an all star ahead of Hamhuis is one of the great mysteries. We can only hope that he finds some consistency at the last couple of year's level come the playoffs.
Rome is doing better on the offensive side than the last couple of years, but is even worse defensively than the last couple of years, and when you look at the top teams in league rankings, you would be hard pressed to find a worse number 5 or 6 defenceman than Rome based on the stats.
From: stats.hockeyanalysis.com
http://stats.hockeyanalysis.com/about.php
For Time on Ice greater than 400 min for 2011/12, 5V5 zone adjusted
...............Overall Rank.........HARO+..........HARD+..........HART+
Hamhuis.............1...............1.390............0.923...........1.156
Bieska................2...............1.333............0.870...........1.101
Salo..................3................1.002...........1.035............1.019
Ballard...............4................0.726...........1.091............0.908
Edler.................5................0.968............0.807...........0.887
Rome.................6...............0.677............1.045............0.861
Similar stats but for the two seasons before this one
.....................Rank.........HARO+..........HARD+..........HART+
Bieska..............1.............1.075............1.097...........1.086
Hamhuis...........2.............1.155............0.986............1.070
Edler...............3.............1.081............1.042............1.061
Alberts.............4.............1.203............0.841............1.022
Salo.................5............1.126............0.891............1.008
Ballard..............6............0.956............1.010............0.983
Rome...............7.............0.869............0.891............0.880
BTW, this year, for Detroit, every number for every defenceman that has played over 400 min is over 1. St. Louis’ numbers are not quite as good as Detroit’s.
HARO: Hockey Analysis Rating for Offense
HARD: Hockey Analysis Rating for Defense
HART: Hockey Analysis Rating for Total (average of HART and HARD)
For these ratings, a rating of 1.00 indicates when the player is on the ice his performance should be similar to league average performance. For example, if a player had a HARO of 1.00, one should expect he will contribute to goals at approximately the league average rate. Anything above 1.00 is better than average and anything below 1.00 is below average. For HARD, 1 is the leagure average for contributing to goal prevention.