Blind taste test on career numbers. In one glass, you have Joe Saunders. In the other, you have another cola, and the bane of a large area of Twins Territory, Kevin Correia. Take a sip!:
In 4927 plate appearances, opponents have hit .276/.330/.433, for an OPS of .763, K/9 of 5.1.
Now, rinse. Have a cracker. Cleanse your palate.
In 4634 plate appearances, opponents have hit .272/.335/.429, for an OPS of .764, K/9 of 6.0.
Balls pulled by right handers are killers for both (.439/.435/.797, OPS 1.232 vs .423/.420/.776, OPS 1.196).
I know they have largely pitched in different leagues and these are just the stats I happened to grab, and I know I'm no Alfred Einstein, but what is the attraction to Joe Saunders? Is it that in 2008, he had a 3.41 ERA and was 17-7 (for a team that won 100 games)? Because if it is, I just can't help but look at pretty much every other year in his career. If anybody has some stats that might change my mind, I'll listen, but until then, I see a left-handed version of Kevin Correia type numbers. And in Target Field, a left-handed Kevin Correia type is worse than a right-handed Kevin Correia type, in my opinion.
Did any of that attempt to account for Correia throwing nearly half of his career innings in the caverns of the NL West?
Joe Saunders by ERA+ over the last three years: 92, 107, 103.
Kevin Correia by ERA+ over the last three years: 68, 78, 88.
Saunders has also thrown 120 more innings during that span and is a year younger. I don't think anyone here is mesmerized by his 17-win season and certainly he's not the ideal counterbalance to their pitch-to-contact group, but he has established himself as a solid MLB pitcher and that's what the Twins need.
I previously looked at the 5 year stats and they weren't all that great of a difference, with many stat numbers favoring Correia. The ERA+ stats for 3 year performance which you cite mask some of the glaring stats that compare less favorably to Saunders than Correia, or at best, similarly poorly. The right hand bat difficulties illustrated above really points to potential looming problems in Target Field. Here are some examples of other 3-year comps that belie the ERA+ differential:
Kevin Correia 5.41K*9/4.26xFIP/.268OBA/14%K%/1.38WHIP
Joe Saunders 5.09K*9/4.36xFIP/.275OBA/13.4%K%/1.37WHIP