[C.A.]

You're still seeing that Haki must be presented in a physical way, expressed in physically observable state. You're saying I'm ignoring the other effects of Haki, but aren't you the one who's ignoring the other effects of Haki?

I've already addressed the physical effects of Haki, I asked the questions:

Can Haki be so strong that even light would freeze in its tracks? Or rather, the one who wielded light, to freeze in his tracks? Can you have such powerful intention in hitting someone that your punch will hurt someone that can't be hurt? Can you will your arrows into splitting rocks apart? Do you have the will to think that you can do these?

Though short, these are the Haki that everyone sees, including those you mentioned. I'm not addressing these because I'm addressing everything else, the entire bulk of Haki that people do not have a clear idea of. If you skip this part and read the rest of my post, that's how big the entire bulk of what Haki is that's not applied physically.

Did WB not show his Haki? No, he has always been showing it, like I said, that reputation of a person and how people would fear his name, is Haki at work. He has ruled over people hearts, his enemies feared him, his allies feel protected by him. Not just his crew, but even the islands that he protects with his name, the Fishman Island which Jinbei holds his gratitude to White Beard for helping.

Why did Robin fear Aokiji so much? Why did the rest of the crew fear this seemingly friendly man immediately after Robin explains who he is?

Why did Kizaru strike fear into the pirates when he crash into the island?

Did the Supernovae not have Haki? Of course they had Haki, though they may all have different levels of Haki, Kid and Law's crew could hold their own against Rayleigh's Haki.

What makes you think WB doesn't have Haki? Because he didn't make people faint, because he didn't use a Haki attack against Shanks? Is there something special in a Haki imbued attack? No, there's nothing special, it doesn't look extra flashy, it doesn't emit light, it doesn't look like its more powerful, absolutely nothing special at all. Its just the same attack, but it goes through.

In all types of forces, there's a difference, when there's a difference, the force travels from a higher potential difference to a lower potential difference. Water flows from higher ground to lower regions. Electricity, voltage is that potential difference, it determines the flow of electric current. Heat, a region of higher temperature will transfer to a region of lower temperature.

Now apply that to Haki. If your Haki is stronger than your opponent(s), your attack will flow through him, how strong is the flow, this current, depends on the potential difference. If the difference in Haki between you and your opponent, he could probably be knocked out by your sheer will. If the difference is small, you may lend him a good hit, but not enough to take him out. If the difference is equal? Nothing happens.

So did Whitebeard not use his Haki against Shanks? He didn't falter at all in Shank's presence, most of his crew as well, some did, but most still stood up even when his Haki is strong enough that even the ship gave way by that powerful Haki. When Whitebeard and Shanks clashed, it is also the clash of their Haki, but their Haki is as strong as each others and neither gave way, 'nothing' happened. Well they say that if you smack two things hard enough, something's got to give way, so, the sky gave way instead.

Haki attacks are not flashy, they don't look anything special at all. They are just powerful, they feel powerful. Because Haki is not seen, but felt. And we have been feeling Haki all the while in One Piece.

People only seem to look at Haki for its physical effects, but that is really just the visible tip of the iceberg. The rest of Haki is much more, all underneath, unseen. What I want people to know is this part that's unseen. Haki as the spirit, the will that's emanating from a person. Haki that attracts allies, repels enemies.

Do continue to question me, because I think you're going to understand what Haki is. Do note I'm not speculating, I'm stating the meaning of Haki. Haki is a word that's in the dictionary and it has a meaning. It is a common word that can be used in everyday speech, because its just a normal thing.