You are confused. I never requested proof of the prohibition. It's unnecessary. We have Ecclesia Dei. Coupled with canon law, the case has been closed for fifteen years.
I cited him because I know people like yourself are more impressed by a Vatican letterhead than you are by the faith itself.
You are mistaken. The faith itself is best lived while in obedience to the teaching of Holy Mother Church. It is you who are impressed with Mons. Perle's letter, not I. It is a bone thrown to a very few SSPX adherents. It points to a very strict condition necessary to exist to avoid a state of sin. Your prolific pixel trail demonstrates that your beliefs and status do not qualify you to meet the strict standards set by Mons. Perle. Together with your total contempt for the Vatican as now run by the the current pope, it is just a fraud for you to use Mons. Perle's letter to justify your arguments. Tsk, tsk, tsk.