Quote Originally Posted by The Crystal View Post
Aerith didn't knew she was going to die, didn't want to, and didn't need to.
Tifa does say that she didn't think Aeris wanted to die at all. But then at the end you see Aeris' face probably symbolizing that she was controlling the lifestream and therefore needed to die in order to return to the planet and do what she needed to do.

As for the arguments being 'laughable', actually I think some of them are pretty strong. This is of course my opinion, but I think a playable character having lines after they are not supposed to is a pretty strong argument to there being some uncertainty of where she was going to die. This does not serve any purpose in testing because they could have done the testing with a playable character.