For a player like Votto I think doubles are a good judge of power. He isn't going to be a guy who is going to turn many singles into doubles by raw speed. His doubles are more a result of well hit balls to the gaps or down the line. They will be a result of him driving the ball instead of a flare down the line. When I see his double numbers down to me it says he isn't driving the ball as well as he has in the past.
I don't know when it became taboo to say that Joey Votto's numbers are down. I think its fair to say that this season has been a little disappointing so far and still think he is a great player.