From what I understand of radioisotope dating, it rarely comes out with the correct date on samples of known age. We assume it works on samples of unknown age. There are dozens of examples of horrendously inaccurate dates published in scientific journals. Even parts from the Mt. St. Helens ordeal have been dated in the low millions.
Without question, regardless of the original denotation and connotation, myth has a negative meaning now. It is indelibly linked with "fairy tale" in the minds of English speakers. Maybe we should develop a new word here and try to get it into the OED.
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The Unpronounceable Krsqk
"Well, sir, at the moment my left processor doesn't know what my right is doing." -
Freefall