How do you mean? I'm not asking aggressively just wondering. Keane, Herrera and Carrick played with attacking midfielders and number 10's in Scholes, Rooney, etc and those players all had a similar role to Bruno in the team. Keane, Carrick, Fred etc role is to get tackles/ interceptions in, recycle possession, keep the ball moving and provide balance. Fred does it well for the most part. Could we do better? I think so.
You might argue that Fred is playing in the worst team of the bunch but those other United sides weren't exactly brilliant either (bar 11-12 season)