From the pattern:
This sweater is a fun way to puzzle your knitting friends. It combines two unusual sweater constructions into one garment, appearing as a side-to-side sweater from the front, and a top down sweater from the back. It is knit in one piece; the only seams are in the sleeves.
The pattern was inspired by the drape of priest's stoles, which manage to lay flat around the neck and down the front, all in one piece.