I'm not super familiar with the history, so excuse me if I say something stupid. Let's say Jamie doesn't get to kill Aerys for whatever reason and he destroys KL. He dies, Jamie dies, a lot of people die. What happens next, what does Tywin/Ned/Robert/ etc. do? Crazy hypothetical, I know but I would like to see the thoughts of others.
Another question is, if Aerys gave the order, would Rossart have gone through with it? For this we would have to assume that Rossart had a death-wish himself, or he had some mechanism to delay the ignition long enough for him to skip town. IIRC, the plan was to place caches of WF all over town, and then ignite them simultaneously. This indicates either a series of fuses or one large explosion, say, under the Red Keep, that would subsequently set off the other caches. Either way, it wou