I don't think that you're getting it, Daniel. He can respect the office of pope without believing that the person commonly known as Pope Benedict XVI is the pope. (But there does seem to be some obscurity in his reference to Ratzinger and the Chair.)
Are you aware of the fact that there are Catholics who do not believe that Ratzinger is the pope called sedevacantists, and Catholics who give serious consideration to the possibility that he might not be called Traditionalists? (I refer to Traditionalists who walk in the footsteps of Archbishop Lefebvre, who on two occasions I know of spoke of a time that might come when it would be necessary to say that the Chair of Peter was vacant.)
If I were you I would not be so quick to invoke the Judge to come against those who refuse to honor Josef Ratzinger as His Vicar. He might not like your doing so. It might rub Him the wrong way on a Personal level. Would you dare invoke Him against a rabbi who mocked Him whom the so-called Holy Father held up as a model unbelieving Jew?
If your faith in Ratzinger's popehood is so strong, and your loyalty to your "Holy Father" is so pure and so chivalrous, you should think twice about being part of a forum in which denunciation of him as a Modernist mischief maker is permitted. What do you think the effect of your censures is going to be here? Do you think that all the sedevacantist "goats" and those Traditionalists who respect their position are going to be cowed and feel sheepish?
There is a certain freedom here. People who recognize Ratzinger as pope and find references to him as "Ratzinger" abhorrent, should find that freedom abhorrent too.
On the other hand, if we are going to discuss making this forum work better as a peaceful and friendly place, we might have to consider finding some way for sedevacantists to be able to comment on matters related to the "pope" outside of the crisis in the Church forum which on the one hand would not cause pointless offense, and on the other would not require them to refer to as pope a man whom they do not consider pope, to say the least.
I suggest a note of relativism: ie: "As a sedevacantist, I of course do not think that it is a pope who has stabbed Chinese Catholics in the back..."
As for how Catholics may licitly speak even of true popes, here is how a Saint, St Bridget of Sweden, describes a pope whom she saw as her Holy Father, if Butler's Lives can be believed: "He was a murderer of souls, more unjust than Pilate and more cruel than Judas."
Was St Bridget wanting in respect for the office of pope? Was her statement disgraceful? We can only wonder what she would have made of a fellow Catholic who became a sedevacantist on the basis of that pontifical murderousness and injustice and cruelty. But I think that we can be sure that her pious jeremiads and invocations of Judge Jesus would have been against the offending pope, not against someone whose revulsion towards his iniquity made him make a serious theological faux pas.
We should reserve soul-chilling references to the Judge to Come to references to the way in which the New Church corrupts the morals of little children in its schools. We do not have in Jesus of Nazareth the kind of Man Who lends Himself to the notion of HIs being a Heavenly version of some sort of secretly Traditional but cautious Vatican-based cardinal who knows the priestcrafty ropes and would not let his personal wrath and disgust over the soul-murders that Rome, at best, tolerates, betray him into imprudent expostulations.
Sedevacantists, Traditionalists, we can ALL agree at this point that "Benedict XVI" is a murderer of souls, more unjust than Pilate and more cruel than Judas. What exactly would stop us from owning up to that truth in the light of the dreadful Judge to Come, Who liked kids and lowly ones and could scarcely contain His rage over what scandalizes them?