If it's mere addition, and going by my gaps, even absorbing the whole Earth's population,
cannot explain the difference between Ginger Cell and the Cell that fought 17/Kamiccolo.
Also, to absorb billions of humans, he'd need decades. However, i'm not against assuming
that Kamiccolo's energy would be a mere addition, because, obviously, that's how AT viewed
Cell's absorptions, he was just not thoughtful enough to calculate how many humans Cell
needed to absorb.