Also... Boswell's formula isn't really based on anything much. You can't assume GIDPs. SIERA does a great job of factoring them in, though, and it doesn't like Lannan one bit.
As for getting rid of Lannan? I don't know that I want to. I think he's showed one quality that's very important in a back of the rotation starter: durability. All the talent in the world isn't worth anything if you're on the DL. There's a reason Boston keeps Wakefield around.