When Thiago was here, he was mostly seen and used as a CM, despite showing on every single occasion that he excels when attacking. During those times, any time you'd put him in Iniesta's LM position, next to a CM, he'd have a great game, visibly better than his games as CM. That's not to say that he can't play CM, but AM or any other attacking midfield position suits him much better. The same thing is even more true of Rafinha. He's even less of a CM, and even more of an attacker. And especially now that even Iniesta's role has changed and been pulled back under Enrique, the same problems are evident when Rafinha plays LM, too. The roles we've gotten used to with Xavi and Iniesta have changed and are more adapted to supporting the attacking trio and covering for the fullbacks. We barely have any room for attacking midfielders any more. Real CMs are a dying breed, and sadly, it seems like any attacking midfielder who shows even the slightest trace of being able to play in that central position is bound to be used there, in shortage of an actual CM. It has to be done, but eventually it will hurt the team, and it will make the player seem worse than he really is. It's a shame.
I know we're short on midfielders so don't take this as criticism of Lucho for playing him that way. Or of other coaches for playing Thiago as CM. I know players are used to fill the blank, and not necessarily to play in the position that suits them best. All I am saying is that, categorically, Rafinha himself would probably benefit most from a RW / RAM position of some kind.