Do Oral Traditions Provide Any Reliable Facts?

Do oral traditions provide any sort of reliable facts? Can they be taken seriously, apart from written corroboration? Well, as i've said before many times in other lectures, very often we see oral traditions that had been dismissed as mere folklore and legend turning out to have a great deal more veracity than it seemed. There are many examples of this, but one big, early example was the discovery of troy in the year 18 70. And whether you consider this plausible, or give it any credence, depends on how you evaluate lore and oral traditions.