Bishop Williamson denounces resistance to be sedevacantist ... or ....
... at least he would if he followed his old principles ... but he seems to like the new ones too much.
When the "resistors" started off, they claimed that they were the carrying on the path of Archbishop Lefebvre. I have read that Fr. Pfeiffer even claims that he is still a member of the SSPX and that Bishop Fellay is his superior.
This is a farce.
The reality is quite different on a number of levels.
Dogmatic: the Four Marks of the Church. Fr. Pfeiffer appears to have been poorly formed (or was napping during class) as demonstrated here and here.
Doctrine: Obedience due to a superior's lawful command. In each case the "resistance" priests either disobeyed such a command or turned out to be sedevacantist. Hence the una cum controversy.
From the founding doc for the sspx-mc:
... A remnant of priests willed to fulfill their Oath against modernism by having nothing to do with such wicked and premature compromise. They began to resist the new liberal tendencies, by simply remaining “a little army of rebuilders”, doing what an army does, fighting, until the new mass is
forbidden, Vatican II anathematized and the old Code of Canon Law enforced again by the Eternal Rome; and Tradition itself, not us, little soldiers, be recognized by a fully converted Papacy....
Here is what what bishop Williamson wrote about this opinion ( True Catholics).
The documents of Vatican II are openly heretical. There is nothing worth salvaging from that Council.Now I see no difference between "Vatican II anathematized" and Bishop Williamson's assessment quoted above.
So if bishop Williamson has not changed ( a mantra of the resistance even as they turn on him ) then the sspx-mc and all the "resistors" that I have encountered have been denounced by Bishop Williamson because their opinions are "moderate sedevacantist" positions.
Practical: the resistors desire something more than a loose association. However good luck with that ... Who gets to be in charge of a group of rebels??? They will only obey as long as it suits their purposes, otherwise they'd still be in the sspx.
Revolt begets revolt, as we see as the 'resistance' turn on Bishop Williamson and rend him.
So what he should do is swallow his pride and apologize to the SG and ask for readmittance to the SSPX.
Then at least something good will have come out of this mess call the 'resistance'.