I can't think of any other reason for the numbers, either. The BC is just something I added to my username back when Tiresias was taken on another website years ago, and I've stuck with it.
In Greek myth, Tiresias is a blind prophet who is, as a rule, ignored, but how he became both blind and a prophet is the interesting part.
Zeus and Hera had a tiff about whether men or women more enjoyed sex. So they turned Tiresias into a woman so he could find out. When they asked him, he told them that women experienced ten times the sexual enjoyment of men. Hera was furious and blinded him, but Zeus, happy the argument went his way, gave him "second sight," the gift of prophecy, in compensation
Myths are a rich tapestry. ;-]