sounds like people are confusing air superiority and air supremacy again. this rule is more realistic to modeling air superiority than in the box rules. air supremacy is when your opponent has no airforce in the designated area. 2 different things…
by the way i don’t like the rule because it gives the attacker too much advantage. for the sake of example let’s say both sides have equal numbers of fighters. if the defender allocates all his fighters to 1 territory then the attacker will have air superiority in all the other territories and a push in the ‘built-up’ territory. if the defender spreads his fighters among several territories then the attacker can send all his fighters to any one of those territories and pick then off the fewer defending fighters one by one with air superiority advantage. put another way, the attacker will always be able to send all his fighters within range to one battle, but the defender doesn’t get that luxury. granted when it’s the opponent’s turn the attacker/defender roles will be switched, but perhaps by that point the damage to the previous defender’s airforce will be too great to make it totally fair. besides, it’s not very realistic pretty much always having the attacker with the air superiority (because that’s what would end up happening).