OK, the second reason for the "division line" is....

[SamIAm]

Originally Posted by CMHCoachNRef

Well, if we truly wanted to reward the defense and create turnovers, why not say if the defense can cause the ball to go into the back court it is a violation?

The defense bats ball into the backcourt and attempts to go get it. Whistle, deadball, no lay-up for the defense, defense (now offense, gets ball for sideline throw-in).
OR
Defenses stop trying to gain possession and start hitting/swing at the ball, after all what good is tip if it doesn't go in to the BC. Results harder fouls as part of the game, and the introduction of volleyball tactics to basketball.

How are those two "why nots"?