What does Darzee's wife do that is sensible in "Rikki-Tikki Tavi"?

The sensible thing Darzee's wife does is help Rikki-tikki destroy Nagaina's eggs.  

Darzee isn't entirely sure about the idea of destroying all of Nagaina's eggs. He has some sympathy for the eggs because his species uses eggs to reproduce, too.  

On the other hand, Darzee's wife knows each of the cobra's eggs has a chance to grow up and be a dangerous predator against man and animal alike.

Darzee's wife then flew within earshot of Nagaina and began faking an injured wing. Nagaina can't resist the easy target, and she begins slithering after Darzee's wife. Darzee's wife keeps the act up while moving away from Nagaina. Nagaina is now completely focused on Darzee's wife and never once considers that she is being tricked. The distraction technique allows Rikki-tikki time to find the eggs and destroy all of them except one.