That is scientifically inaccurate and a myth. Ask any eye doctor.Not all peripheral vision skills are lost under stress. If that were true, the defenders direct vision would only be able to see something as small as a laser dot which we know to be incorrect. With certain threat focused skills taught in the classes, the range of peripheral vision is within 2-4 inches of line of sight, well within the range of tunnel vision should it ocurr under stress.
Learn this: It is not possible to consciously see simultaneously with both peripheral vision and central/tunnel vision. You mistake 'alternating' the two separate 'seeing' systems with each other and believe that is peripheral vision sighting. But in fact, it is either one or the other.
We see objects by using central vision, we navigate (subconsciously) by using peripheral vision....our visual outer oval.
Imagine walking through a low cave or an attic. You are focused ahead looking for danger or an object. You hit your head on a rafter or a rock above your head. That happens because you are using central vision and your peripheral vision has been suppressed.
When stress forces a threat focus...the peripheral vision system goes blind. Period! It cannot work in conjunction with threat focused central/tunnel vision.
You cannot 'will' peripheral vision. You cannot use peripheral vision to aim, you must use central vision to aim. You can point shoot at a target all you like, from hip, chest, below line of sight, etc., but good hits will be a result of muscle memory/habit/practice/trial and error....not peripheral vision acuity.
This is a detailed subject, but the bottom line is that peripheral vision is, indeed, a rather weak point shooting asset or training aid.
People should learn to silhouette or slide aim and definitely get a laser sight because of all the variables of a self defense encounter.
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