sati ca kalpite vācakatve varaṃ varṇabhāgā eva santu vācakāḥ kimadṛṣṭāḥ sphoṭāṃśāḥ kalpyanta iti
If expressiveness is to be assumed, it would be better that the phoneme-parts themselves be expressive - why should unseen sphoṭa-parts be assumed?