I thought it was one of those that was harshly viewed, as I said there was a lack of creativity in it but I think that was something Fletcher was growing in to and as you said it came at a point where Carrick was going through a slightly lull and so they weren't at their best at the same time. The other problem is that it came at a point where we lacked the attacking options we had now and had over the last couple of years. If I recall right it was mainly in the 2010 season where we were heavily reliant on Rooney for goals, with Berba not quite clicking. Plus in fairness neither have amongst posters favourite players. Fletch eventually won over the majority but think it's only in recent seasons that Carrick has won over most.
I think with Carrick coming out of his lull and being more imposing these last few seasons that creativity issue wouldn't have been a problem, but also with the addition of first Hernandez and then RVP/Kagawa, allowing us either Rooney/Kagawa to play just ahead of them then we wouldn't have had that same issue either, plus I think part of the problem in the last season and a bit with some of the wingers like Valencia is needing them to play from deeper due to needing them defensively to help the midfielders and a lack of range, with Fletch and Carrick they would be able to control the game better and Fletcher's presence for me would have freed up Carrick to use his range more and let the likes of Valencia push higher up the pitch where he prefers to play.
I mean I can see where people were coming from that it wasn't the most exciting but I think it was something they were both growing in to and with the attacking options to the squad over the last couple of seasons it would have got better. Plus tbh it'd still be a big upgrade on what we've had this season/last season.