The February issue (WW 04-45) gave the results of my systematic search for coincidental self-synonymy: pairs of words that are unrelated etymologically but via convergent evolution happen to be spelled the same and c. mean the same. I extended the coverage to near-synonymic pairs as well and to unrelated contronymic (self-opposite) pairs.
Word Ways: Vol. 37
, Article 18.
Available at: http://digitalcommons.butler.edu/wordways/vol37/iss2/18