One thing about having the characters debate something like this as we would is that the very reason Susan is willing to give this subject serious thought is the same reason their plans will inevitably wind up being significantly different from zombie survival strategies people in our world might come up with.
Granted, in our world, Sarah's plan has as much chance of success as many of the ones I've heard discussed.
Sarah's pose in panel three may look familiar to fans of Avatar: The Last Airbender and/or The Legend of Korra. Sarah is deliberately posing like a lightning bender. I'm not sure how you get lightning from fire bending, but I can dig it.