Final answer:
The departure of Macbeth or Lady Macbeth from the castle court to perform deeds alone creates dramatic tension and provides a window into each character's psyche, emphasizing their distinct reactions to the unfolding events and foreshadowing their eventual downfall.
Step-by-step explanation:
The effect of having Macbeth or Lady Macbeth leave the castle court at different times to carry out a task while the other waits is a dramatic technique that creates tension and highlights the characters' individual responses to their crime. When one character leaves, the audience is given insight into the other character's thoughts and feelings through soliloquies or actions. For instance, as Macbeth goes to commit the murder of King Duncan, Lady Macbeth waits anxiously and reveals her own trepidation and resolve in her soliloquy, indicating her role in the plot and her influence over Macbeth. Similarly, when Lady Macbeth exits and Macbeth is left alone, his soliloquy reveals his deep inner conflict and foreshadows the psychological torment that will plague him. The separation of the characters hints at the eventual disintegration of their partnership and their mutual crumbling under the weight of guilt.