I know what you mean.
Justin Verlander, Jered Weaver, Francisco Liriano, Jonathan Papelbon, Houston Street, Roy Oswalt, John Lackey, Francisco Rodriguez, etc.
There are quite a few pitchers who start off with a bang. I don't believe any of the above players mentioned posted minor league numbers like Clay Buchholz or threw a no-hitter in there 2nd start (other than Verlander none have thrown a no-hitter).
Not just that but who cares if he is a Cy Young candidate or not. There are plenty of good pitchers in the league who are not considered for the Cy Young and for the most part its because of the team they play for and the record they have.
Clay Buchholz is in Arizona working on strengthening his arm to get ready for the season, not to mention he has the arsenal to compete, and the attitude to deal with the pressure of Fenway and Boston. Last its nice to have a cheap option in the rotation with stud potential while Santana is here for a season before he cashes in and we owe more money where we might not need to.