What caused (again, from the perspective of the SSPX) the docuмent to lose its "canonical directive"?
I believe it has to do with the Code of 1917 -- i.e., once that code became law, cuм ex no longer held.
Reference? Is it in the 1917 Code?
cuм Ex. was quoted as a reference (source) for cn 188.4.
I think we should distinguish in the Bull the eclesiastical laws (penalties etc) from what is of divine law. As far as the first ones is concerned they were all abolished by the code, but with regards to the divine law, they weren´t (they couldn´t actually) be abolished, and cn 188.4 is of divine law, when it says that a non member cannot have ordinary jurisdiction in the Church.
The 1983 code abrogated the 1917.
Yes, if you believe JPII was Pope.