No, it's not a novelty. Bellarmine actually speaks of the distinction between the designation to office as the material aspect and the conferral of authority as the formal aspect of an individual becoming the Pope. For an individual to become Pope, he's elected and accepts (material) and then God bestows the papal authority on him (formal). In nearly all cases, the two happen immediately, but if there's some impediment, God doesn't bestow the authority. This is what is meant by "valid election" in these texts which aren't dealing with it from the perspective of the material/formal distinction, i.e. an election where the elected receive Papal Authority as a result.
Can you please provide a quote of St Robert Bellarmine stating that the designation to office is the material element? The only quote I've seen is referenced by Fr Desposito and in it St Bellarmine refers to the PERSON as the matter, which is in a certain. Way disposed by the election. To receive the form. This is not identical to the position of the Guerardians (or semivacantists as I call them.) I
If you have any proof for the assertion that the dozen or so canonists cited, when referring to an "invalid election" are in fact referring to someone being validly elected but posing an obstacle to the reception of papal power I would love to see it.
The Cassiciacuм theory as presented by MHT does not agree with your assessment of those texts, as I indicated. They admit that all of these authors are stating that such people (women, insane men, heretics, unbaptised etc) are incapable of receiving the "material element" ie designation. They hold that Bergoglio is not a heretic in the sense indicated by said authors, since he has not been declared as such. They assert that Bergoglio is in possession of a valid designation by way of a valid election and that his "lack of objective intention to will the good of the Church" vitiates his acceptance of the office in such a way that he retains the designation and does not accept the office of pope. This is yet another novelty, since one who is elected but does not accept cannot retain the designation indefinitely per canon law.
Perhaps reread Fr Cekada's article "Bergoglio's got Nothing to Lose." He demonstrates that such men receive no title or designation whatever precisely because the election itself is invalid.