Board Thread:General Discussion/@comment-25672219-20170405004515/@comment-27701762-20170405022310

This explanation not only massively complicates what is already an originally simple explanation (since the historical plaques in Waterfall specifically say that humans are so powerful that it would take almost all monsters to equal the power of one human, which is something further evidenced by the end of the True Pacifist Route), but it creates massive inconsistencies and raises massive questions about the game's world.

Positing that the power to reset is what allows the humans to prevail essentially says that the humans tried and failed, so they just keep resetting until they got the desired outcome (there's insufficient evidence to say that a monster with a human soul is actually so incredibly powerful that it alone would be able to fend off all of humanity). But we already know that the power to reset isn't a case of individual people undoing certain events that they were part of. It resets the entire world. And because it resets the entire world, only one being - the one with the most determination - is capable of exercising this power. So if humans had the power to reset on the Surface, there would be only one human who did (or else there would be multiple humans continually resetting the world), and it would need to be the case that that one human was in charge of the human offensive against the monsters. The incredible number of requirements just to get an explanation that isn't "humans are a lot more powerful than monsters" means we are jumping through a lot of hoops for basically no real payoff.

Addtionally, it creates a lot of inconsistencies with the game's lore: if humans innately have the power to reset, why can Frisk only reset back to the point when they fall in the Underground? if humans can innately reset, why doesn't Chara use that power when they are fused with Asriel to prevent their death? if humans can innately reset, why wouldn't this be mentioned at some point about humans, since it would essentially have to be a pretty open fact that they had this power?

In contrast, the line you point to has a much simpler interpretation: we already know that when the timeline is reset, monsters retain some memory of what happened previously (see lines from Toriel, Papyrus, and Undyne about the protagonist or their actions seeming familiar). So when Frisk says "Asgore, you've killed me before," Asgore nods not because he has some knowledge about how the power to reset works and is secretly acknowledging that this power was why the humans won the war, but because he has an actual memory of killing Frisk and is saddened by it.