The idea of trading Mauer comes down to one simple thing for the Twins; can they resign him. Mega stars are getting traded these days under these types of situations; Teixeira, Santana, Sabathia, Lee, and even A-Rod, just to name a few. I am not sure where the certainty that he won't be traded is coming from.
I can understand the point that we don't need a catcher so why trade for Mauer. I just feel this is a worthwhile upgrade. Buchholz and a prospect or even 2 can be replaced. Mauer can anchor the Sox for years. In a way, I actually hope the Twins find a way to keep him but my fear is he is headed to the Yankees after this year.
I still say this is good value for the Twins and keeps them competitive, maybe even more competitive, and they are all players the Twins can actually afford to keep around for a few years.