I feel bad for laughing, but I think its pretty funny that Aspi said “NO SCREW SIMULATIONS” and then Baba came along and said, “NO, SCREW YOU, ITS ALL SIMULATIONS” XP
Anyway, I guess the biggest question for me now is… why was Kotarou on the Moon?
I sat here for a long while contemplating everything, and suddenly had an “ah-ha!” moment. And then it turned into this whole theory… well, enjoy:
“The Earth was once filled with life originating from a meteor. As time passed, humanity was born naturally. Then they were destroyed before colonizing space, and had to re-evolve. By that point in time, the Earth was on the verge of drying up, so some of the aurora flowed to the Moon, where fresh material was still available. This is how the garden was formed.
That was fine for a while, but then the Moon dried up as well. By then the Earth had recovered somewhat, to the point where one more attempt at evolution seemed like it might just be possible. this the aurora flowed back to Earth.”
- Memories: 007: Kagari (Earth)
There was something huge that had always bugged me about a certain character: Sakuya. He says it himself, that he was the previous Kotarou, the one who could Rewrite himself. But then there’s something about that happening thousands of years ago… and yet the humans in Sakuya’s memory are acting the same as if they were modern-day humans. That just does not make any sense… Unless you consider the above quote.
The answer: Sakuya was one of the “first-humans”, lets call them. As he told in his memories, and as the Memories section tells us, the first-humans were faced with Destruction, and failed. Sakuya being the being that he his, Rewrote himself into a tree, and passed on into the next cycle of humans, lets call them the “new-humans.” (Shizuru’s route is essentially a repeat of this, except humanity survives in "a place safe from the Destruction. A new humanity would not have been able to re-evolve anyways, because after all, that was a failed simulation.)
But then the aurora realizes something: there’s not enough of this “fresh material” that the aurora uses to sustain life for this next cycle to fully evolve. So the aurora hops over to the Moon where it can survive while it waits for the “fresh materials” to recover on Earth. But it seems that the Moon (i.e Kagari) knew that the “fresh materials” on the Moon would only last long enough for the Earth to recover enough for one more attempt at evolution. So, using the property of the overlapping worlds due to the much smaller service area of the Moon, it started running simulations (yes, on the Moon) to determine the optimal equation for evolution to occur fully on Earth, since there was only one more try.
So how does this answer why Kotarou is on the Moon? I’m getting there. Now, I dont have lines to justify my next assertion, but I think it makes sense logically: Just like the Kagaris are incarnations of the Moon and the Earth, I believe that Sakuya and Kotarou are somewhat of incarnations of the aurora. Assuming this is true, remember that when Sakuya/the aurora fails and humanity is destroyed the first time, some of the aurora flows to the Moon. And bingo! Not only does this explain how Kotarou got on the Moon, it explains why Sakuya and Kotarou can both be incarnations of the aurora and exist at the same time (because Sakuya stayed on the Earth in the form of the tree).
This also explains why Kotarou remembers all of the simulations. He is the aurora, and it is the property of the aurora to create overlapping worlds when the celestial body doesnt have enough surface area. All those overlapping worlds happened for him, but they did not happen for the Earth.
So then to answer the “when does this all occur in the scheme of Rewrite” question, what happens after the solution is found is as follows: Kotarou/The aurora flow back to the Earth. And the Earth restarts from scratch, following the formula, this time happening in the way Terra plays out. So the simulations do not occur at the moment of the choice not to attack Kagari, but before the Earth restarts one more time.
By the way, I really like the idea of calling Moon route the Kagari route in this way. Because it really is such a romantic story. The aurora (Kotarou) is in love with the Earth (Earth Kagari). But the aurora fails. Instead of letting the aurora be forced to leave, however, the Moon (Moon Kagari), the Earth’s sister, not only sacrifices herself so the aurora can stay, but works endlessly so that the aurora and the Earth can be together. While the aurora is waiting, though, he falls in love with the Moon as well. This makes it all the more tragic when the Moon has used up all its energy, and while the aurora now gets to go be with the Earth, he must leave the Moon behind forever.