No.  I believe that a Traditional Catholic who believes that a legitimate pope who is in possession of his authority and execising it freely can corrupt the Church's Magisterium, the Public Worship of the Church, and the cult of the saints to the degree that we see at Vatican II, that is in fact heresy and guts the very foundations of Catholicism.  It's more akin to Old Catholicism than to Catholicism.

It's not my problem that you don't understand basic distinctions.  I am not a dogmatic sedevacantist.  My personal opinion is that the See was not in fact vacant from 1958-1989, but was occupied by Cardinal Siri as Pope Gregory XVII ... and I'm not sure after that.  It's possible that Ratzinger was legitimately elected, but couldn't fully realize the protection of the Holy Spirit because he wasn't a bishop (due to invalid episcopal consecration), and therefore had no teaching authority.  Bergoglio labors under the same problem, but there's also a chance that his election was rendered null and void by the conspiracy to get him elected.  If you want to say that Paul VI was blackmailed but a legitimate pope, go for it, or even that he was locked away in a dungeon while his imposter double did all the damage, more power to you.

Father Chazal does not "identify as" a sedevacantist (and he's not), and I consider his opinion to be very solid (and not even remotely heretical).

But I urge you to abandon the heresy of attributing the destruction of the Church to legitimate papal authority that has been freely exercised (vs. under durress, such as blackmail).  Vatican I clearly condemned that supposition as heretical, that remaining faithful to the True Faith might justify and even require separation from communion with and submission to the Papal Magisterium.  Please wake up to how pernicious and heretical that supposition is.  This is an act of charity on my part to try snapping people out of these heretical notions lest they lose their faith entirely.

you condemn other traditional Catholics here. Fr. Chazal never does that. NEVER. He is a Catholic and a gentleman.

In fifth-century Athens, a Greek philosopher named Diogenes the Cynic used to walk around the Acropolis in the middle of the day with a lantern, appearing to look for something. People asked him what he was doing, and he said he was looking for an honest man.

I don't know if he ever found what he was looking for, but if he did, I think he felt very much the same as I did when I read your post above.

Kudos, my friend, I'm glad I've finally found someone else around here who knows that. A one-eyed man is king in the land of the blind. Here's your monocle!

I have been to one of his Masses and there is not a sedevacantist check. Perhaps he would react differently to infamous individuals he recognized, but I don't know.

That's right. Theologians before vatican 2 wrote that even if the pope or the pope and bishops teach something in a non solemn manner, it is infallibly safe to follow.

Question? Is there a difference between Anti- Pope and vacant seat people?

More evidence of what, my disagreement with Lad theology?

Go ahead, read Vatican I's Pastor Aeternus, then post what you find and stop blowing hot air that's riddled with deceit to suit your narrative. You won't post anything that even remotely teaches the NO doctrine of all the bishops in unison with the pope are infallible - because that's a new doctrine found only in LG. You keep posting the same old lie, now put up or shut up.

Oh, and for the record, you already knew that I only reject only certain teachings of certain theologians of the last few centuries, not all of them.

I'm not sure what you mean.  Those who believe that the See is fully vacant would hold that the V2 papal claimants are in fact Antipopes.