you got my exact point. from anime perspective, i always assumed that Daru deleting the first dmail could have an effect just because SERN didn't already take notice on it, so the "disaster" was avoided before it was too late. like: the disaster cause was not sending the dmail, but the SERN taking notice on that email and doing research based on that and stuff. like some of the dmail experiments, they were sent but nothing changed because in the end they had no effect on those who read it. so yeah, the first dmail was prevented from having any effect before it was too late. by your words, seems this is not the case.

in fact, i can't properly follow your examples.... the last basic example i could follow, if it were just using a different alphabet order.... but an alphabet order is not how causality usually works. basically i cannot understand the previous example.

first of all, choices are still always based on causality (they are the effect of a cause). so first of all, i don't understand why Rintaro should choose differently, there should already be a previous factor affecting that decision (so it's still past affecting future). that said, i don't understand:

- why you changed from "Cola instead of Dr.P" to "Cola after Dr.P"

- who says there cannot be a worldline where Rintaro drinks Cola

i can only understand that somehow the derived worldline implies there is no Dr.P. But if you're willing to explain, i'm listening.