Although this is true I think the thinking is that head trauma ends fights more often than punching to the body. However, sweeping and following with a punch is also worth three points, which is very practical for the street. Instead of trying to score big with kicks to the head, I think you should train your students to score big with sweeping and striking a downed opponent with a strike. Wayne Otto is the best ever at this and he is one of the greatest point fighters ever. He is also one of the few who could probably handle himself in any fighting arena.