I think it does matter. If Blackburn can recover his sinkerball mojo, then he can again be a very good starter. It would be sickening to release him then watch him go to the Yankees or White Sox and do well while the Twins are still paying him. I would rather try to send him down, or failing that, persuade him to go on the DL. Maybe the training staff can be asked to help him by bleeding him with leeches, in which case he might legitimately need to go on the DL.