Phrases like "the #1 rule" or "... is job ONE...." or whatever are just rhetorical flourishes to emphasize an important point.
They also immediately open the speaker up to argument and petty one-upmanship as wags flex their wit at the speaker's expense.
"...Hey, the first rule of a gun fight is to have been born in the FIRST place, so you even exist to get into that gun fight! ...."
"Oh yeah? Well, if your MOMMA hadn't been born, YOU wouldn't have been born, so the VERY first rule of a gun fight is that your granddaddy and grandmother have to have met..."
In other words, these are rather inane things to say or even think about in terms of "rules" and checklists.
All the principles we discuss relating to self defense are important. Any one facet MIGHT be the one that keeps you alive.
So, what's the point of this poll and this thread?