Two ways this goes as long as he's here:
- He's intermittently injured but that means he sticks around and contributes well as a squaddie without leaving us short.
- He's intermittently injured but we pretend he's not going to be, so we end up short.
It's got nothing much to do with Tomiyasu as a character or a player, it's up to Arteta and Edu to cover us properly. His situation is not the same as Partey (for example), firstly because he's not end career, and secondly because when he's out no one's sitting on their hands claiming his return will fix everything.
So there's no problem with re-signing him. I just hope it's on sane wages. Other than that it protects his value, he's only 25 and we'd make a profit if we sold him.