To be clear, the actual trade is Marion Barber III and a 12th rounder for Rashean Mathis and a 6th rounder. So the guy trading away Barber, can still keep his 4 players, chuck away Mathis if he wants (or hold onto him without impacting his keeper list) and also add an extra 6th rounder. If he holds on to Mathis, he'll end up losing a draft choice 2 spots higher than where he was drafted last year...so if Mathis was drafted last year in the 13th round, Mathis would basically be the guy's 11th round pick this year. If he was added off of the free agent list during last year, he will end up losing an 8th rounder this year. But then again, he doesn't have to hold onto him at all in which he'll just get thrown back into the free agent pool once the keepers are disclosted and still have that extra 6th rounder.