User blog comment:GAMEONBOI/How strong is deku/@comment-35197848-20180924120800

It might be possible that Deku's "100% Full Cowl", was in fact not 100% of his full power. Granted, there's not much evidence to back this up, but you could also say this about this powerup actually being 100% of One For All. When Deku used his 1000000% Delaware-Detroit Smash, he wasn't actually using 1000000 percent. It was just a rush of adrenaline added onto his full powered punch. Who's to say this is not the same sort of thing? I might be completely off, but whatever. That's my theory.