I just finished reading the paper, and it is pretty good. I like how it is long enough to cover the theory and its adherents sufficiently, but short enough not to be a bore.
I think the main thing one needs to understand and take from this article is that sedeprivation adherents judge the internal forum. And, the church cannot do that. Yet, it is essential to their reasoning. The paper said that because these novus ordo popes do not have "the intention" to guide the church as Christ dictated, they cannot be pope in act, only in potency. Because, true popes act according to Christ in virtue of his promise. And, this "intention" to guide is synonymous with the end of the papacy. And, the end of the papacy is a papacy in act. But, because these novus ordo popes acts are bad, their intention is bad, and therefore they are not popes in act or true popes. They can only be popes in potency.
Do you see the problem? The adherents to this cassiciacuм theory judge the internal forum(ones intentions), and the church does not do that. It is essential to their reasoning and their existence. It is for this reason that it is not a catholic theory, and that those adhering to it are doubtfully catholic.
This is a dangerous thesis. It puts a pretty face on top of an ugly monster. The monster is sedevacantism and usurpation of authority that is always doomed to a conclavism once fully matured.