Nanami Kento Punches Up

Haven't been able to get the idea that Nanami is essentially a video game character stacking buffs to punch higher than his weight class.

He hits waaaaaay harder than he probably should under the right circumstances, and I want to get a rough estimate of how hard.

The math is something like:

(80% (CP) + 40% (OT) + ?? (SYH BV))*?? (RH)= TSP

CP: Clocked in normal power which is ~80% of his unaltered normal strength.

OT: Overtime buff which is 40% of his normal unaltered strength

SYH BV: Show your hand binding vow. The in universe explaination for why ANYONE does the anime trope of telling others how their powers work. Is there any guidance on how much of a buff this gives?

RH: Ratio Hit. I think of this as a standard videogame crit dealing double damage, but I imagine I've overlooked a more precise answer.

TSP: Total Striking Power. How hard he actually hits once all these conditions are met.

Assuming Show Your Hand gives a similar boost to Overtime (pure guess) and Ratio is literally a crit (reasonable assumption) the math is like:

(80%+40%+40%)*2= 320%

So Nanami hits with more than 3 times his normal strength under the right circumstances, and this is assuming he doesn't hit a Black Flash. If he does then the scale goes nuts. Black Flash is an EXPONENTIAL buff. It amps his strike to the power of 2.5, which if you spend even a moment thinking about it means Black Flashes are... silly powerful.

Am I making any bad assumptions here? Messing up my math? Is this whole analysis dumb?

EDIT: Black Flash is very weird. Because we don't know what the smallest unit of cursed energy is or what unit we are using to measure it at all, trying to do an exponent (namely "to the power of 2.5") is impossible. We could have a completely asinine multiplier or a miniscule one.

If we, purely for the purpose of this, want to take it as a multiplier of 2.5 rather than an exponent that means we take 320% * 2.5 to get 800%. This would mean that a black flash from Nanami with all of his other buffs would equal eight times his normal striking strength which is pretty awesome.

Safe to say that this is probably a low ball of how hard black flash hits, and if we do consider it to be just another kind of crit, that means that Nanami is stacking crits as well as buffs. Even cooler.