[MENTION=16942]BBZ8800[/MENTION], why do you say about classical RBs, who play more conservatively, but still well in their job's description so to speak, that they are dumb? Fullbacks aren't exactly the most creative players on the pitch, their job is usually pretty straightforward. Just because we happened to have a rightback which redefined the roles tied to that position at Barca doesn't mean that what he did somehow becomes what others must do. You call them dumb, I call them normal.
Just like with Xavi, with Alves the player was the role. You can't have the same role re-assigned to other player and expect him to give you as much as all time greats do. What you need to do is take the loss in quality, or redefine the role.
'Too dumb to get involved in some complicated slow possession based attacking options'. Is that the criteria that makes you dumb at RB, them 99% of the players on the market are either dumb, or bad in defense because they are not natural RBs.