Okay, I know that the cast that is created doesn't cover the knuckle area, so let's not revisit that unless you really want to for some reason.
What the cast does do is support your metacarpal bones, it's why Floyd fought exclusively in Vegas where the practice is legal. The metacarpals, as designed by nature, are fairly delicate and are not efficient at transferring energy to what your hand is punching. With a normal wrap there is a certain amount of give in your hand, with a layering of wrap and tape a rigid cast is created around your hand, there's no give. It's like the difference between using a metal bat vs a wooden bat, it's subtle but it's not nothing.
Also, Canelo, unlike Mayweather, doesn't appear to have brittle hands. Canelo is throwing full force with no fear of catching an elbow or hurting his hand on someone's hard head. If Hearns had used this wrap against Hagler, maybe he knocks Hagler out in round 1 instead of breaking his hand.
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