What might have been Kushner's motivation to present the events in Act II, sc. 9 as a split scene?
I think that the split scene technique and the almost simultaneous nature of both couples' breaking up contributes to the overall theme of change and transformation that underscores the entire drama. The idea that human beings must endure change, and that progress on both national and spiritual levels is defined by this element of change is what drives the action in both scenes. Joe and Louis are animated by the need to change their lives, necessitating the breakup. Louis feels he needs to be honest with himself in that he can no longer give what it is that Prior needs. Joe feels that he must be direct with Harper in which he indicates that he no longer can care for her or that he has feelings that bind him to her. Both men display angst with change, unable to repel it and oddly uncomfortably in embracing it. The recipients of these messages are agents that struggle with such change, reflecting Kushner's idea that change and transformation are difficult forces to accept, but inevitable when they present themselves. Prior and Harper both stand hurt and stunned with change. Despite standing at the "threshold of revelation," it still hurts to be rejected and to deny it and, thus, deny a part of what it means to be human is where the location of pain resides in both of them. Displaying this as a split- scene enables Kushner to thematically explore an idea in different contexts, showing its complexity and its universality in one vibrant instant.