Let's go back one step here.

Before the tragic events of September 11th 2001, most airports and airlines around the world were enforcing a total ban on any baggage over 20 kg and British Airways managed to convince the Regulators to permit 23 kg. Because of the enormous pressures on "the aviation business" after 09/11 and the fight to survive, the 32 kg allowance was retained for Brazil (their government threatened to stop foreign airlines from flying) and for premium customers.

The emphasis on "nothing over 23 kg" remains and if "ordinary" customers insist on packing heavy bags, a penalty "Heavy" charge will apply if a bag is 23.1 kg. If you have a 2 piece allowance, distriubute the weight more evenly - simples!