Continuous use does not freeze tradition — vernacular languages keep changing
Rome adds: their traditions survived intact by continuous use among Christians — like vernacular languages, which endure even without grammars because a people keeps speaking them.
Experience says the opposite. People are inconstant; whatever lives only in use keeps changing, often slowly and unnoticed — unless something else holds it fast.
Their own analogy proves it: vernaculars continually shift until, after centuries, they look like another dialect. Ancient customs diverge from today's for the same reason.
Church history shows the same: set the second- and third-century Church beside Rome's present rites and discipline, and the gap is obvious.
So the Church needs a firm, stable rule that does not hang merely on memory and good faith — a rule by which creeping abuses can be corrected. That rule is sacred Scripture alone, not unwritten tradition.
Latin
XXXV. Addunt Pontificii traditiones suas conservatas fuisse, & ad nostra tempora integras pervenisse per continuum usum in quo apud populum Christianum fuerunt; quemadmodum, inquiunt, conservantur linguae vulgares, etiamsi nullae quandoque exstent grammaticae propter earum usum continuum in aliqua gente. Sed contra est experientia. Sicut enim homines natura sunt inconstantes & valde mutabiles, ita quaecunque sunt in eorum usu, nisi quid aliud obstet, hoc ipso continue mutantur atque alterantur; licet plerunque sensim & sine sensu. Quod manifestum est ipso exemplo quem illi afferunt. Etenim linguae vulgares perpetuo mutationem aliquam recipiunt, quae post aliquot saecula ita notabilis est ut videantur in aliam dialectum transiisse. Et ita quoque in quolibet populo antiqui mores, & consuetudines ab hodiernis plurimum discrepant, saeculorum lapsu semper rebus humanis mutationem aliquam afferente. Idemque facile animadverti potest in Ecclesia ipsa Christiana. Si quis enim peritus historiae Ecclesiasticae, ob oculos sibi ponat Ecclesiae faciem, qualis erat secundo & tertio post Christum saeculo, prout illam ex istius aevi scriptoribus colligere licet, agnoscet statim Ecclesiam Romanam in ritibus & disciplina hodie multum ab ea distare: nec est qui negare possit istis in rebus magnam factam esse mutationem. Unde magis patet necessitas regulae cujusdam firmae atque stabilis, nec simpliciter pendentis ab hominum memoria & bona fide, ad quam corrigi possint abusus & errores in Ecclesia sensim enascentes: qualis regula est sola Scriptura sacra, minime vero traditio non scripta.