I didn't claim he was flourishing under LvG. I supported him coming here and feel he could've contributed more than the likes of Fellaini last year. He's probably not the best option if you want to illustrate a player who didn't work out. Choose Liam Miller, Djemba-Djemba, Kleberson for that.
The broader point is that fans don't know what is in Mourinho's strategy, what characteristics he's after when he evaluates positional needs and the players who may fill them. Given that, you can't just randomly offer up players you like and then get angry that Mourinho isn't buying them. Its his call based on what he wants.
Well if I just wanted to take it to extremes of bad decisions I could ask whether people should have been "called out" for their incredulity about Bebe, but I decided to stick with more similar situations of managers re-signing players they've had previous successful relationships with.
As for your broader point, Bravo was chosen for fitting a certain set of positional needs - it doesn't change the fact that the sceptics were right. Not to mention the fact that it is obviously legitimate to question managers' ideas about positional needs. Plenty of people were quite sceptical about van Gaal's insistence on left footed centre backs for the left side of central defence (Mourinho seemingly being one of these people).
These critics may be right or wrong, but it's daft to just close down criticisms of signings or systems by saying van Gaal/Mourinho has a master plan and he's the manager so he knows best. They are perfectly capable of having debatable tactical preferences and fallible views on how to fulfil them. Enough of this "so you think you know more than Mourinho, do you?" stuff.