Carrying should be one element in a larger set of strategies. I actually agree with the author on #1. The best laid plans of mice and me often go astray, as the saying goes. Nothing wrong with asking God to have your back, and it should be the first priority anyway, in case you get called unexpectedly to Heaven, via knockout game or whatever.
But as for the element of surprise, that is something you can reduce. War is thousands of years old. We should be pretty good by now at finding adaptations to what amounts to a very simple surprise attack. First on that list, as others have said, is to avoid the war zones when possible.
Second, while you cannot have eyes in the back of your head, you can have the next best thing, a moving head. Look around. Note where everyone is. Notice where surprises could come from, and create a buffer of space. Distance gained is reaction time gained.
Third, if the surprise comes too close to draw a firearm, be prepared to defend your head. If you survive the first attempted blow and can create some space, you still have a chance to pull the firearm.
Failing that, use lesser but more quickly deployed weapons. A tactical knife comes to mind. Don’t disrespect the effectiveness of a knife in close quarters. It is at least as likely as a gun to do the necessary defensive damage.
Also, as the author of the article states, do study the films. They are helpful. In one, where a teacher is hit in an alley, I observed several things. First, just as the teacher is passing the mini-mob, he actually lowers his head further, looking more or less directly at the ground. This was, IMHO, a submission behavior, like a dog rolling on its back and baring it’s neck to the alpha. It is disgusting to see in a human. He could not have been surprised if he had looked the group right in the eyes and communicated by body language he was ready to engage whatever they had.
Furthermore, had he been watching those closest to him, he could have seen the attacker coiling behind one of his friends getting ready for the attack. Once you are trained to see it, it is very difficult for a would-be attacker to NOT telegraph their intentions. There is always preparation, and it can be observed. But you have to be looking.
Another thing. It helps to be listening. When I was a young man I was waiting for someone at night outside a fast food joint. I heard step coming up rapidly behind me, and turned just as the attacker arrived. The element of surprise was gone, and the situation was diffused. Your ears can be the eyes in the back of your head. Field tested.
But there’s another thing here. Some young computer geek could make a fortune right now, figuring out a way to creatively use something like Google Eyes to give people “eyes in back of their head” for those long walks home alone in the dark. The timing for marketing this couldn’t be better, and the tech should be pretty simple. I’d love to see the commercials for this. Take those home burglar alarm commercials to a whole new level.
I've had that same experience.
I had a similar one that was actually a bit comical, on another occasion. I was on a date with a girlfriend at Fisherman's Wharf in SF. We were walking along together and I just sensed that there was somebody following me, way too close, intentionally being quiet.
I spun very suddenly, ready to fight. It was a street mime, who'd been mocking me. He almost collided with me. When I spun he backed way off and put up his hands in 'no harm meant, I'll be leaving now' fashion. We had a good laugh about it later.