Recent work on the funerary chapel of Amenirdis I at Medinet Habu has proved her selections from the Opening of the Mouth ritual to be deliberately chosen and meticulously laid out on the walls of her funerary chapel such that the texts, which were inscribed in retrograde, commence at the doorway to the chapel and culminate on the innermost wall of the corridor surrounding her cella. This interpretation of the layout of OM scenes suggests that the scenes inscribed on opposite walls run parallel to each other and should thus be read concurrently rather than sequentially. While this theory differs from more conventional interpretations of the division of the ritual, it accounts for the scenes' layout, their retrograde direction of writing/ reading, and relates the scenes' textual content to their physical location on the walls of the chapel. A new system for numbering the various scenes of the Opening of the Mouth arose from this particular analysis of Amenirdis's texts. The new numbers incorporate the scenes' physical location on the monument on which they occur.
Ayad, Mariam Dr., "Towards a Better Understanding of the Opening of the Mouth Ritual" (2007). Sociology, Egyptology & Anthropology Department: Faculty Work. 4.