Board Thread:Questions and Answers/@comment-28898329-20160901162911/@comment-27701762-20160901185708

There's nothing in particular that is really dispositive of the issue, in either direction. The theory has some interesting pieces of evidence, but one of its problems is that the pieces are often very specific: if you look at the narration here, you can see it as being Chara, but does that hold true at all points, or at least a sufficient number of points? I've never sat down to actually investigate whether the dialogue more broadly corresponds to the expectation set down by the Chara-as-Narrator theory.

I'm not even sure there can be evidence against the theory, since in order to have such evidence you would basically need a direct statement on either A) who the Narrator is, or B) who the Narrator isn't.

In the absence of such a direct statement, the null hypothesis would be that the Narrator is simply an invisible third party observing the adventure of the protagonist. The question wouldn't really be "is there evidence that the Narrator isn't so-and-so," but "is the evidence that the Narrator is so-and-so sufficient to reject the null hypothesis."