I'm not sure you're aware how high the probability is that Hernandez has better results than Stroman over a 20-inning sample. It's much higher than 0. And those 20 innings don't move the needle at all on the probability that Hernandez will be better than Stroman over the next 20 inning sample, which is why you wouldn't keep Hernandez over Stroman regardless of what happens over the next three weeks.
The issue is that he might be able to blow people away with just a fastball in 1-inning stints. Sanchez might be the 3rd best reliever on the team. You don't want to waste him in AA in a contention year if you can get 70 good innings. Especially when he's a long shot to be an effective starter.
7x7, 12 team draft March 16 at 7ET. It's a league with people who have no idea what they're doing, and hilarity is likely to ensue. If you're a sadist and this appeals to you, let me know.