The original user was mentioning that he put the binding for the total weight on the cart display page to display the total weight. The problem was that this will only display the total weight for the first item in the cart, to get all of the items weight you would use the total column around it like the example code.
You would use this anywhere that you would like to have the total weight of the entire cart and not just the first item in the cart. The update would be make in the code view, you can just wrap the function around the total weight value you already have.