I don't disagree that Jackson and Grienke are better than Lannan. I just am hesitant to go 5+ years and $18MM AAV for Greinke that I think he may command as a free agent, plus the loss of a 1st round pick, and I wonder about whether Jackson is a good signing at 3 years and $40MM that I think he's likely to get.
As Lannan is in his last year of team control, I'm not sure when he'd have to be offered arb to keep him. I think it would be after our exclusive rights to Jackson expire. I would first see if I can sign Jackson to more team-friendly terms, but if I can't, I might be able to live with Lannan as an MLB average kind of innings eater at the back of the rotation for a year. The fellow I might not bring back would Gorzellany, who may be in the $2.5 MM - 3 MM range. I would look to Meyer, Purke, Rosenbaum, whoever in 2014, not 2016, which is when a slot would be open if we brought back Jackson at 3/$40MM.