It's vitally important to understand that when the dogma was declared in 1950, Pope Pius XII didn't just "make it up" or depart from Sacred Tradition in any way. He instead officially ratified what the Church had believed for centuries. How do I know this? I use an old Missal from the 19th cent. for private devotion & spiritual reading AND the feast of the Assumption of the BVM is listed therein. So so-called 'hyper-papalists' who claim the Pope has absolute authority over the Faith are wrong, The Holy Father can only safe-guard & guarantee the Faith, NOT CHANGE IT!