If the Mariners were truly interested in Porcello, my preference would be to trade Porcello for Franklin....and/or a young pitching prospect that could pitch at AAA, and be called up to spot start when we needed him.
Despite all my unrealistic trade propositions, I've been contending all along, that if we trade Porcello, it would be for young controllable players. I'd think in this circumstance, because Porcello isn't going to net the team any kind of significant delta in improvement, DD's priority would be to have players with controllable years that could fill certain holes that appear imminent on our roster near term.
There is no way Seattle would be interested in Boesch now that they have Morse, Jason Bay, Saunders, Franklin Gutierrez, Raul Ibanez, that Smoak kid, and I'm probably missing some....too many OF/1B/DH types.