Originally Posted by The Joker
It would have been much better than Selina doing it. She didn't have to kill Bane to show she had redemption. The fact she came back to help Batman save Gotham was more than enough to show that.
Yeah, but for the climax of the movie you need that extra dramatic punch to really hit a point home, especially when you're trying to set up Bruce and Selina ending up together. Selina showing up and saving Batman from Bane has a lot more punch to it than her just showing up and chasing some Tumblers. She deserved that big defining moment, especially because she had collaborated with Bane and his army earlier in the film and was partially responsible for Batman getting the beating of his life.
Maybe it could've worked without her doing it, but I still feel like as a character she deserved it. Especially because Batman had already defeated Bane in the way that mattered.