Narcissism? It’s a article about self-introspection, so it’s hardly surprising that first-person pronouns occur a lot. And his described purpose for writing such a document is to better understand his behavior and thus improve his relationships to others. A true narcissist wouldn’t care what other people think.

Sure, but I think you’re missing the point a bit by reducing it to narcissism. For, ahem, me, it’s about strengthening all my relationships, which is nice for everyone involved.