Good advice.
Too bad that Rome added a LOT more 'traditions' after this was penned.
---but you must make a distinction between Apostolic Tradition (which all comes from the Apostolic era -- the Apostles themselves and their co-workers, companions and disciples like Timothy, Titus, Barnabas, Silas, etc.) and lower-case "t" tradition, which could be later and could vary, e.g. whether the Sign of Peace is to be observed with a kiss or a handshake.
Some of the kids do a thumbs-up, but I don't think this is traditional. :o).