I guess you could say that BB7 are 'dual adjustable' in that the inner pad can be adjusted; but the inner pad does not move during braking. So BB7 are slightly easier to set up than BB5, but otherwise work the same. The caliper works by the outer pad bending the rotor until it contacts the inner pad. It's a recipe for warping the rotor out of true, and the more gap between the inner pad and the rotor, the worse the effect.