This team only has 13 bodies for the O-line this spring, 11 scholarship. Can't even go three-deep, so I wouldn't be surprised to see Hale over there just for the spring. He's a rising SR and doesn't need the defensive reps quite as much.
Taking Hale from the DL still leaves them with 15 players, 12 scholarship (and two of the three walk-ons were on scholly at other B1G schools). Most importantly, the next men up (no matter where Hale ends up in the fall) include Donovan Munger and Mike Hill. Munger wasn't medically cleared at all this season and Hill played early but was injured seriously enough that they sat him to preserve his RS when Schutt returned. These two guys are way behind and need all the snaps they can get..harder still since you have Carter and his Beard around as well.
I wouldn't read into this that Hale is being passed up on the defensive line, and perhaps he may impress on the OL? But all-in-all I think this ends up a temporary move.
NOTE: I didn't put Chase Farris in either of the above counts...I don't know if he actually tore his ACL but mid-December surgery makes it unlikely he's back for spring. If anyone has more solid info, please let me know.