Agreed, if you have a FB and HB in the same position (left, right, or center), the HB will get all the carries. If you want the FB to get a few carries, but you HB to get most, put HB center, and FB to either side. If you want fairly equal distribution, put one on left, the other right and both either HB or FB. Otherwise, the HB will get more carries up the middle than the FB.