OK, thanks. My problem is that I just couldn't imagine a hangfire where you can hear the primer go off, followed by the uncertain delay. If that's a possibility, then yes I want to use hangfire protocol if I hear a funky pop. I'd be freaked at encountering a squib anyhow, but before this discussion I figured that I'd be mainly concerned with being very sure to cease fire.
On hangfires (which are as rare as hen's teeth, right?):
I can imagine hangfires coming from dud primers, topped with powder that coincidentally cooks off after a few seconds in a really, really hot chamber.
I can imagine hangfires that come from a wedged firing pin that breaks through the asphalt in a filthy action, and strikes the primer with enough force to fire it. (Maybe unlikely in inertial systems, but never say that circumstances can't invent the perfect filth that allows it).
But has anyone ever in recorded history managed to re-create primer hot-spot hangfires in lab conditions?
I'd love it for someone to be able to create hangfires on demand, and get high-speed radiographs like the Manhattan Project movies of an implosion.