>>546411274
Shadowheart did forget who her parents were and that she's not really an orphan. She did forget her own name. The mirror did work - for almost 40 years - so claiming it had no effect at all on her is blatantly incorrect. While it is true that people are largely shaped by their memories, personality traits and a sense of right and wrong can survive even targeted memory loss or amnesia, as is the case with the Dark Urge. This "Urge" only exists in contrast to a moral framework - without one, there'd be no tension or internal conflict. Tav is the blank slate, not the Dark Urge.
Sentient beings are not software - they don't reset to factory settings after being hit on the head hard enough. The shy little kid who likes flowers and cute little pets could have plausibly survived repeated mind wipes. Shadowheart doesn't even need to be special for this to be true. You're free to roll your eyes at how the Nightsong scene plays out, but ultimately, how Shadowheart is convinced in the moment is a narrative choice, not a logical oversight. This is like the Frodo meme where you ask why the giant eagles didn't fly the Ring to Mordor. Because we would have no story arc had that been the case.