1st TTM Autograph Requests of 2012

I sent out my first TTM autograph requests of the year out this week to spring training facilities. I made a list of the players that I wanted to send letters to this year. I sent 5 letters out to Joba Chamberlain, Rafael Soriano, Aaron Hill, Chris Volstad, and Neil Walker. A couple of those are close to sure bets. I would be thrilled to get the Joba request back. Typically, I will send 5 letters out at a time just to make life easier and continue doing so throughout the year. Any advice for who to send to during the rest of the year?