Fall Guy

He is 32, looks like the boy next door and answers to the name of a Washington suburb. He is a graduate of a variety of Eastern private schools and has a degree in audio engineering, a mean rock-piano style and a reputation of sorts as a soccer player for Bard College. But it was not until last fall, when he stepped before the cameras on Saturday Night, that Cornelius ("Chevy") Chase discovered his full potential. He fell over. Slowly, gracefully and with complete abandon, Chevy's 6-ft. 4-in. frame crumpled to the floor, accompanied by the giggles, then laughs and finally...