I don't see anything from Pereira that I didn't see from Cleverley or Tunnicliffe or Possebon or any other number of midfielders who just were never going to be good enough for this level.
His position last summer as the leading midfield prospect was easily taken by McTominay over the course of last season, who himself is at best a solid prospect. About the only thing you could definitely say is that Pereira has a great free kick. That's it.
Cleverley carved out a fairly solid career for him self over at Watford, probably would have been held in higher regards by our fans if SAF stayed for another 5 years.
I don't have any problems conceding that McTominay is a better talent then Andreas, our squad is big enough for both. As I see it, McTominay is better defensively, while Andreas is better offensively, so the fact that Mourinho played McTominay over Andreas is a given, as Mourinho likes strict organized defenses (in my opinion). It is also worth noting that last season the team was in disarray with changing manager mid-season, and Andreas was never given much offensive responsibility, as he was competing foremost with Pogba in that department.
Andreas also got one thing that Pogba lacks, the correct mentality to make it as a United player. Good work ethics and good freekicks, where have I heard that before? Given a chance, I think Andreas can develop into becoming one of the best creating midfielders in the league, and there is a path open for him now. Anyway, i'll drop it now.