For a second let's leave stats out of the equation. Last season I believe it was Gorman that made a comment that stuck with me, that great teams take on the personality of their defining player.
If someone asked you to describe this Celtics team without naming any one player, I'd imagine these would be the most common descriptions: outstanding defense, efficient offense, intense, team-oriented, attitude, edgy, unselfish. Before last season, I submit that those words would not have been used to describe any of the members of the Celtics except for Kevin Garnett. And ALL of those words would have been used to describe KG. This team has been made into his image, which is why Gorman called him the defining player.
That said...Allen is balling out of his mind right now, he's playing exactly the way I expected he would entering last season (which really lends credence to his statement that he played all of last season injured). And he (along with Rondo) are probably playing the best this season with respect to their expectations. I wouldn't necessarily call that a team MVP, but I would call it outstanding and if both of them keep it up (with no injuries) this team is ridiculously good.