Nice link and I thank you for putting it up here for everyone to be able to understand what threat focus is all about lostone1413.
I've bookmarked it in several areas so I can get back to it. I believe it has a lot of merit as well. I had not seen or known about this until your link, but I'm certainly glad you posted it up for us.
It works on the same principle as the military rifles that use the rear aperture, and that has always brought excellent results as we know from history.