Not so. We have ancient Greek and Hebrew manuscripts to use for translation purposes.
Word of mouth is inherently and notoriously unreliable.
There is no valid comparison between using almost 2,000 year old manuscripts and claiming that something has been passed down faithfully by word of mouth for almost 2,000 years.
Oh but it WAS written down, and quite early at that. Catholics just don't have the audacity to call it SCRIPTURE.
They had 'traditons' for HOW many years before they compiled the bible?
I wonder why they didn't slip them into it when they were the only game in town?