Abuse in Sparring - Has Any Fighter...

When somebody goes "KO" it is because their brain gets smashed too hard against their skull, it happens when your skull accelarates too fast thanks to a punch or another blow.
Headgear doesn't stop your head from accelerating.

An average head weighs between 4.5 and 5 kg. I suspect boxers to generally have bigger heads.
Headgear weighs 300-350 gram.
That would be adding another 7% weight(for an average person), I don't see that as significant enough to reduce KO power in punches by a wide margin.

I suspect boxers to generally have bigger heads because they're men and the average probably include women, generally bigger men (especially the HW division, bigger people are more likely to have bigger heads), and boxing favours big heads because heavier heads are harder to accelerate (makes it harder to score a KO blow)

Head gear is for preventing cuts, not knockouts or brain trauma.

 

I agree on the main purpose of head gear being to prevent cuts...but i do think that it gives some extra Cushin, which should, in theory take off some of the force. I have even heard people claim that smaller or bigger gloves make no difference in punching force..and they have so called studies that prove it. But for me...getting hit with 8 oz gloves is more forceful than 16, and it also seems like headgear takes a little force off.

 

Sure I read somewhere think it was Toxie Hall who said that he used to have to where some kind of football protectors type things around his midsection to protect him against the body punishment from Rocky think he said he broke a rib one time even wearing them atsch pretty sure Toxie never went down in sparring tho and think he might've put Rock down himself once in the run up to the Cockell match