This is the point of my statement. If we set the shoulder back and make a longer neck, the bullet doesn't protrude into the powder space. But, by setting the shoulder back we lose even more capacity.

There are good reasons for moving the shoulder, and the cartridge is a good one. But, the perceived gains in powder capacity are illusory. If the overall length is kept the same, and the cartridge diameter is the same, the cartridge with the shorter neck will have the greater capacity, even if the bullet extends below the shoulder.