I quite like him but this doesn't make a lot of sense. He's an all-round midfielder, definitely not a DM. As a Pogba replacement, he'd be a bit of a disappointment (and it really doesn't seem like Pogba's going anywhere anyway.) As a Pereira/Lingard replacement, he'd certainly be a step up, but he's really too high profile a signing to get such a low-profile position in our squad. That said, he's not really so good that he automatically gets in ahead of McT or Fred, both of whom have been excellent this season.
If Ole has convinced him to come as an effective Pereira replacement and if he'd be happy to really have to fight for his place like that, and if we're not paying over the odds for that kind of squad-improving signing, then I'm all for it! Title challengers have players like him on the bench. But it seems like a lot of ifs.