This refers to the phenomenon of the supremely annoying and sadistic older brother, after Wyatt's brother in the popular television program "Weird Science."
My brother was so totally a case of the Chet syndrome: he used to pull the heads off of my Barbies, take my panties to school to show his useless and creepy friends, "borrowed" my CDs forever, and hogged up the bathroom by showering until all the hot water is gone and I would have to shower cold. Brrrr!
The rarest genetic condition known to man. A person suffering from C.S. siphons the bad luck out of an area and displaces it to himself. Often good to have around on Friday the 13th. Also cursed with extremely bitchy/money grubbing dominant girlfriend. Girlfriend is also most commonly described as a Susan
"Shit, he fucked up his leg, but I just found 10 bucks, that's a severe case of Chet Syndrome."
"Man, his girlfriend is a money grubbing whore, he has such a horrible case of Chet Syndrome."