Hanley returned to post solid numbers. You moved him from his initial position to LF and then 1b. Moving him off the diamond altogether forces him to adjust again. And a lot of non players don't understand the difference, but being a DH is VERY hard. You feel disconnected for 90% of the game. It takes time to develop into a DH, and some guys do it better than others. I wouldn't f*** with Hanley, especially with Ortiz leaving. Leave him at 1B, get a guy who is already seasoned at DH or rotate it to keep your kids fresh
And I speak from personal experience. I was a college 1b, power hitter. My senior year, our SS, who was our captain, blew out his arm and supplanted me at 1b. I became the DH and it was f***ing miserable. Eventually, my production cost me my position in the lineup entirely. It's a different rhythm, a different role. You've got to balance the feel of not playing with the feel of hitting 3-4 times a game. I was awful at it. Some guys cannot do it. You just got Hanley back, got 30-110 out of him. Don't f*** with him again