Sunday's discussion question got a good response. If you didn't already know, Pitcher A is Adrian Salcedo of the Minnesota Twins, and Pitcher B is Stetson Allie of the Pittsburgh Pirates.
I ended up voting for Allie since he has a higher ceiling, and at that stage of their careers I think that trumps Salcedo's superior command. However, while his ceiling isn't as high as Allie's, Salcedo's floor is likely higher. In other words, Allie has a greater range of possible outcomes due to his arm strength. He has a better chance of becoming a star, but his chance of being a total bust is probably higher than Salcedo's.
However, it is a close call, and next year if Salcedo continues to pitch well and Allie doesn't, that opinion could change. In terms of grades, I think both are likely to rate as Grade B- prospects in the 2012 book, albeit for very different reasons.