If you think that Fred did not have defensive responsibility when playing for Shaktar then you might have watched the games but you did not understand what you were seeing.
You yourself even posted earlier in the thread that: "Stepanenko was the more defensive-minded, but there was not much of a difference." Which is wrong in itself (both players shared the defensive responsibility) but still more accurate than what you posted above.
If Fred is not to play defensively for United then we should not have bought him. He is worse than all our current midfielders (apart from Matic) as an offensive player. We could have saved ourselves £50m and used Herrera, Pereira or Fellaini in a midfield three instead, or spent that money on any of the countless midfielders who would play the position better than Fred can.
I did not state that at all. Every player in modern football has defensive responsibilties.
But Fred was never a great defensive player, even in the Ukrainian league. He worked great together with Stepanenko who is a terrific defensive player. Its why the combo worked out so well at Shakhtar. A successful double pivot more often than not consist of one offensive and one defensive-minded player. Organisation-wise they will have the same tasks but they will carry them out differently.
You were and I guess still is arguing that we should play Fred as a sole # 6 and essentially let him play between the CBs in the possession phase, and protecting the CBs in the defensive phase.
That was what I was arguing against. Defensively he is not nearly good enough positionally to play there to begin with. You also need some size in that role, especially in the PL.
Also his passing game (which is one of his strengths even if it can be risky at times even further up the field) is far to risky to be employed in the position.
You would also remove his pressing game which is another of his strengths, since a sole #6 is much more about positional play than pressing.
Its just a really dumb idea. It would even be better to put Pogba there.