> In my IT experience, anything requiring manual human checking basically doesn't get done I fully agree - that why I like this idea; it doesn't rely on humans

> In my IT experience, anything requiring manual human checking basically doesn't get done I fully agree - that why I like this idea; it doesn't rely on humans actively doing something, and instead engages the subconscious. Because our brain is constantly making predictions about everything we perceive, we tend to notice (without trying) if something subtly violates those predictions. We see this effect when people describe how they felt something was "off" or "wrong" before some big event. They probably did see something important, but not enough to recognize it or parse it consciously. Engaging the warning system that our fight-or-flight reflexes - which is very effective at processing visual sense input - is probably one of the more practical ways of getting past in this "humans won't bother" category. Also, a visual-hash isn't really trying to be perfect anyway. It's just a trick that would be very easy to implement. It won't get anywhere close to catching all attacks. It would probably catch more than our current strategy of doing nothing. When you start from 0, any improvement helps. The only reason not to do this kind of scheme would be if it raised the costs, but I doubt that would be a problem given how much headroom we have in modern hardware.