Forgot to mention it was
1 handed CoA block.
Not even 2 handed like Law vs. Doflamingo, or 3 Admirals at the same time using 2 hands vs. WB's long range random Tremor attack:
BB using only 1 hand means BB still
had more CoA power than that, its not even his limit.
I think S-Hawk not being able to use Haki wouldn't make sense if it was that way
considering Fujitora think they don't need Mihawk when they have S-Hawk:
Not being able to use CoA would be depowered,
so without CoA Haki S-Hawk can't replace Mihawk, or they somehow replaced that problem with another method.
Can swordsman in One Piece cut a mountain without even amplifying their sword attack with Haki?
We've never seen that before.
Considering the size X density of the mountain rock vs. the size X density of a human size steel,
cutting the mountain should require much more power than cutting human size steel.
So it doesn't make sense that S-Hawk cuts mountain without Haki, or if they find another method to replace CoA with DF or some kind of another technique.
Otherwise Zolo wasted his Haki for no reason even when he knows he won't be able to hit Pica's real body, he used CoA to cut Pica's Golem, means that Zolo needs CoA to make that kind of big sword slashes otherwise there was no need to waste his Haki.
If we consider that S-Hawk didn't use Haki, and cut the mountain with sheer physical strength, then its still incredibly impressive.
Because that would require MORE PHYSICAL strength than a swordsman with CoA Haki would require. Meaning that S-Hawk's slashes are physically should be more powerful than other swordsman, give that Hakiless Burgess sword skills do that, or that Nightmare Luffy could be an example for it but then cutting Oars a little bit is no where near as impressive as cutting a mountain.
Why physicality is important? Because we've seen that with much superior physicality you can overpower even Ad.CoA barrier.
Hakiless Pre-TS Luffy's attack is not working vs. Marigold's Ad.CoA:
Blocks easily.
Hakiless Pre-TS Luffy's G2 attack vs. Marigold's Ad.CoA:
Hakiless attack overpowers the CoA Haki barrier.
Considering Luffy's
Hakiless G2 attacks were no where near close to destroying a mountain, anyone can do the math about the Haki level difference.
Or when Katakuri's CoA was > Luffy's CoA,
Luffy managed to overpower Katakuri's superior CoA with much superior
physical strength difference via G4 form.
Much superior physical strength overpowered superior Haki.
BB's 1 handed CoA block (not even 2 handed fully powered) > S-Hawk's mountain level insane physical strength amped slash (if he has no Haki and no DF amplified) , if S-Hawk has CoA Haki its also impressive in any case.