John Thompson III entered Madison Square Garden on Saturday morning not knowing how his team would respond to a two-game losing streak in which the 19th-ranked Hoyas scored 48 points in each game and were throttled at home in the second. He found out in a hurry. Georgetown took a 23-point lead in the first half and cruised to a 67-51 victory over St. John's, showing flurries of offense and a superior defense.