I didn't have any of those guys in my plans either. Dipoto is capitalizing on uncertainty - guys in the upper minors have books, while guys in the low minors are preferences, draws at the deck as Doc would say. Front offices that liked Brayan 2 years ago should still like him - he hasn't had a chance to fail yet. It's a little annoying to basically trade 4 players to get a Mike Montgomery type back, when what we got for Mike in the first place doesn't seem to have a place with the Mariners either, but that happens.
My preferred way to grow starters in the minors is to seed the farm with a lot of them. Dipoto is just saying "keep the top 3 and trade the rest, unless one of the top three can get me a TOR starter who is about to blow his arm out, then do that."
If we do add Gray I'll just wish him better luck than Smyly had.