Here are some of the numbers he used: Garza: 3.05 BB/9, 7.1 K/9, 1.09 HR/9, 38.9% GB%, 4.39 xFIP Harang: 2.57 BB/9, 7.4 K/9, 1.47 HR/9, 35.1% GB%, 4.21 xFIP He adjusted them for league, as well. Garza may have a high ceiling, but if you put any stock into xFIP, he's been pretty underwhelming in three full seasons in the majors. I know he might get a positive boost for switching leagues, but he'll likely get a negative bump for having a much worse defense behind him. Unless Hendry and his scouts are convinced he'll continue to outpitch his xFIP by a decent amount, there was no reason to give up Archer. Even if he does, I don't think you give up Archer.