This character caused great distress to many people, so in response, the great Boba Fett/Magneto/Seifer/GM Cool Guy along with Spymaster, Ad Avis, Ice Trey and Mad Monk decided it was about time to fix his little red wagon.
Thus, The Coolness was made in a satiric attempt to poke fun at "The Sickness" and his brother "The Illness".
This was, of course, before "coolness" was even a viable word for internet or real life usage. Years down the road I hear it all of the time. It caught on very quick. While I don't think I can claim origination of the word, I can definitely say I spread it to a large portion of people on Lake Superior. Especially that wonderful, Y-Wing shaped town of Moonglow. :-)