This past weekend we had a field umpire who, with a runner on first, always moved to the "C" position. In my mind, and that of others, he missed a number of calls at first on plays he felt first baseman came of the bag and didn't find it again (lots of dirt piled around the bags and they were covered in dust). Neither dugout gave him grief, but fans of both teams did. Is there some reason I'm not getting that he would have set up at "C" with a single runner on the bases and that runner being at 1B?