Aron's only statement concerning imperfect consonances is that, unlike perfect consonances, a composer can place an unlimited number of these intervals in parallel succession. Pietro next purports to tackle the tricky problem of beginning a composition of four or more voices. Writing one voice at a time forces the composer to use large leaps, voice overlap, and rests. The translation, however, is completely unclear and contradictory, and the entire chapter seems rather pointless given Chapters 21-30. A perfect consonance does not have to begin a composition, but must end a composition.
Dissonances can be 'hidden' within ornaments providing that the first and last notes are consonant.
As stated previously, there are few restrictions on where to start the chant, evidenced by the wide range of starting points in the diagram. In this usage, the tenor is not a voice, but a note above the final. The tenor and final together bound a 'characteristic interval' of a mode. This will become known as the repercussio later in the century, and should not be confused with a confinal or the concept of ambitus. With this in mind, the diagram on p. 33 makes much more sense, as it gives just enough of the chant to establish the tenor pitch.