Here is why I say it isn't a balk. I re-read Section 1, Art 3 which says, "[n]atural preliminary motions such as only one stretch may be made. During these preliminary motions and during the set position until a delivery motion occurs, the pitcher may turn on his pivot foot or lift it in a jump turn to step with the non-pivot foot toward a base while throwing or feinting as outlined in 6-2-4 and 2-28-5." Because he made a jump turn, granted in a 270 degree movement, it is not a balk just the same as a jump turn 90 degrees isn't a balk.