Comment: The voice is too "heavy." Cornelius lightens it up using la la's. The exercise induces the tongue movement at the tip to be flexible enough so as not to interfere with the sound.
Quote: ...the tongue functions in a dual capacity during phonation. Its forward part, or blade, must be free-moving for the articulation of consonants, whereas its root area, which forms the forward wall of the oropharynx, must maintain a constant adjustment in order to sustain a constant vowel quality. It is this physical and neurological independence that enables the singer to produce a legato flow of tone which does not interfere with the articulatory processes, and that prevents articulation of consonants from interfering with the free flow of vocal tone. (A Dictionary of Vocal Terminology)