CathInfo.com

So you can make a judgment that the "pope" is not worthy of your obedience but you can't make a judgment about why he is not worthy of your obedience?  It's not that hard to research the issue. 

Easy, logical Catholic argumentation for sedevacantism (and what is already utilized by everyone in the SSPX, Resistance, and Chazalian-sede-but-it's-not-really-sede-otherwise-people-would-get-upset camp).

Yeah.  Sound Catholic doctrine.  What's the big deal, I wonder?

If there has been no pope since John XXIII or Paul VI then there are no more bishops with jurisdiction which means no more apostolicity which is one of the four marks of the Church. This is heretical.

First of all, bishops with jurisdiction (ordinaries) is a separate issue from a vacant Roman See.  You could still believe that the Roman See is vacant without asserting that all the other sees are vacant as well.  The sede vacantist position only asserts that the Roman See is vacant at the moment because the Novus Ordo apostate claiming the see is not capable of possessing the office.  Sedes don't all agree on the status of J23 and even if most of them do agree that he was a heretic, they don't all agree on whether or not all the other sees are vacant.  Second, please provide a source for your contention that all the sees being vacant at the same time is equivalent to an end to the mark of apostolicity for the Church.  It's pretty bold of you to go around accusing people of heresy when you haven't even established that they have indirectly denied a dogma never mind that you haven't even begun to establish that sedes deny the necessity of the mark of apostolicity.  I assure you, no knowledgeable sede denies that the Church will always have the mark of apostolicity.