This gets to the heart of Fr. Johnson's error that caused him to conclude that the new rite of ordination is invalid. He mistakenly thinks that the rite itself - meaning the surrounding ceremony - is what give the meaning to the form, in such a way, that if the ceremony does not sufficiently signify that the person is being ordained to the priesthood, it will be invalid. This is a common error today. What gives the form its meaning are the words that constitute the form.
The adjunctis (surrounding prayers of the ceremony) can help give the form its meaning if the form itself does not sufficiently determine the matter, but the form, as such, does not derive its meaning from the surrounding ceremony. If it did, it would follow that baptism administered using only the matter and form would be invalid, since there is no ceremony to give the form its meaning.