Just to be clear, the thread title was tongue-in-cheek. No, I don't really think he's our best pitcher, but I wanted to start a discussion about the fact that he's been pitching so well you could actually make a case for that proposition.
I think including 2011 in your timelines is a little misleading given that we know he was hurt by then. And using 2005-2011 as the period for K rate, but 2007-2011 as the period for walk rate, constitutes cherry-picking. His walk rate as late as 2010 was better than it was in 2005, but none of the variation in that period was huge; he's gone back and forth over his career between a reasonably low walk rate and a very low one.
On the K rate side, what appears to have happened is that he changed his approach in 2007 to pitch a bit more to contact, with notable drops in both K and BB rates that year compared to 2006. From 2007 on, the K rate did continue to decline, but very gradually until 2011; his 2010 K rate was closer to the 2007 number than the latter was to the 2006 number.
I agree that it's unlikely he'll post a career-high K rate when all is said and done, even in this K-happy era. But are you really saying that the fact he declined from 2005 to 2011 means he must continue to decline, even in the aftermath of TJ surgery? No partial recovery of this skill (such as it was) is possible?