Now let us leave these two examples for a moment to consider the interdiagetic nature of both Michel Gondry's Eternal Sunshine of the Spotless Mind and Ben Briand's "Apricot." In both of these films, clever assemblage is used to place the character in relationship to himself or herself. Through "L-cuts," the protagonists voice is played over scenes of their past selves; Far from being the narration of a memoir, however, we come back to see the characters themselves speaking the words in question. Both narrator and memory exist as characters. However, only in Eternal Sunshine do the characters encounter each other. Joel stops talking and moves from narrator to memory in a seamless moment, whereas the female protagonist in "Apricot" never comes into contact with her memory. The doubling is not 'substance encountering itself.' In these two examples our theory holds -- Eternal Sunshine can be said to be comedic, but "Apricot" cannot.
I'm still troubled by William Wilson, however. Perhaps the work is a comedy? Perhaps a 'substance encountering itself' is necessary but not sufficient for comedy? Further reflection along these lines is needed.