What is important about the tales themselves?

The tales themselves (except for large passages of the prologues and epilogues) are largely told in the words of the tellers: as our narrator himself insists in the passage. The words stand for themselves: and we interpret them as if they come from the pilgrims' mouths. What this does - and this is a key thought for interpreting the tales as a whole - is to apparently strip them of writerly license, blurring the line between Chaucer and his characters