The problem is that it muddles the conversation and gets us into Oliver projections. All prospects have the same dollar attachment to them. So in the end it really comes back to your projection of them as a major league player. Teams that deal established talent for prospects do so because of financial restraints, so the relevant issues are - what are the finances for the team, what is the team's objective, how do the prospects project. Surplus value just deflects into irrelevant tangents. This is not a "rare commodity". If it was - Willingham would have long been dealt. 34 year olds who have a history of health issues, can't field, and aren't having career years do not possess a lot of value. You seem to think the only place to find these type of players is on rebuilders, but teams calling up prospects also move these players. Take Aoki last week. Jason Kubel is available and would fit their park better. Same with David Murphy. They could sign Choo. Corey Hart. Logan Morrison is available. Lucas Duda. I could go on and on. Plodding, position-less, aging players are not exactly a rare or premium quantity people are knocking down doors to get.