Alt is short for Alternate Account. You should never make one, unless you like having a ten point infraction. Britishlanguage made two obvious alts, because he's a dipshit, and was banned for it.
Or you could just hide them better. Or not use your personal account as the referrer. Sling's alt lasted two years before Sushi banned it in February 2013.
You'll never guess WizardTrubbish's alt despite it having been banned a while ago.