Who would be an example of dogmatic NO sedeplenist? I always equated sedeplenism with R&R, but maybe I am wrong.
There is a difference and a nuance, but I don't care to get into a long explanation right now.
Suffice to say: there are dogmatic sedevacantists, who consider non-sedevacantists to be in need of conversion, the Catholic Faith, etc. On CathInfo at least, the phrase has been well-defined, explained many times, and has entered common speech.
So it's simple to contrast that with "dogmatic sedeplenists" who are exactly the same, only about the statement "the Seat is full" instead of "the Seat is empty".
And that's precisely what Sean said ("I would ban every one who does not hold Francis is the Pope plain and simple."), so it's simplest and safest to conclude he is a Dogmatic Sedeplenist.
Saying he's dogmatic R&R would be guessing or going out on a limb. Perhaps a solid limb, but a limb nevertheless.
I like to stick to facts as much as possible. And again, I'm a stickler for accuracy and also simplicity, whenever the two are compatible.