Odd, you talk about “SSPX folks”. There are ordained priests, a few lay brothers and sisters and that group is the SSPX.
If laity espouses sedevacantism, they are schismatic in their belief, but they are not SSPX and the SSPX has denounced that belief here: http://www.sspx.org/sspx_faqs/q15_sedevacantists.htm
You know, in a funny way this is an example of what I've been saying. There are people saying they side with SSPX to avoid tipping their hand as being sedevacantism which is a perfect example of the fractures that are facilitated.
If they're in full agreement with the dogma of the Church, what's the issue that led them to the point of seperating themselves in the first place, having some members excommunicated and then having that lifted and so on? I don't see how they're in full agreement and yet deciding whether to be in agreement or not.
They're obviously not in full agreement with something or else there would be nothing to negotiate.
Following along from the link you provided, here's a sentence that will make you do a real double take when you're reading rapidly:
The cunningness of the Devil knows no boundaries!
Cunningness isn't as commonly used as a similar word. Anyway, I hurt my eyeballs zapping them back across the page to that sentence then started laughing. Just shows how often some formerly unmentionable things are now mentioned.
Regards