Yes, it is a very overrated and overused argument. Especially when people use it as a magical tiebreaker by assuming that the center provides more to his team defensively. While this is certainly true for some centers, people use it as a blanket statement. For example, I'm sure you can find numerous posts on this site (going back several years) of people claiming Stamkos is better than Kane because he is a center. When really, Stamkos does not provide anything defensively that Kane does not by virtue of being a center. If a player is capable of driving the offense from the winger position, he is as valuable as the guy that lines up at center offensively.