If you're about to get in a fight, it's important to use the center of your field of vision, because that's the only part that's worth a damn.
For a quadruped, you can see the head, and forelimbs. You get a lot more information from the head.
I was taught, when sparring, to 'loosen' my vision and look a little lower, roughly between the pectoral muscles. But that's bipeds; there's more to track. The stare-down pre-fight behavior was already well-established, and still matters for quadrupeds, many of which are dangerous, so there's been no evolutionary pressure to change it.
If you're about to get in a fight, it's important to use the center of your field of vision, because that's the only part that's worth a damn.
For a quadruped, you can see the head, and forelimbs. You get a lot more information from the head.
I was taught, when sparring, to 'loosen' my vision and look a little lower, roughly between the pectoral muscles. But that's bipeds; there's more to track. The stare-down pre-fight behavior was already well-established, and still matters for quadrupeds, many of which are dangerous, so there's been no evolutionary pressure to change it.