@Greg:
Is it just me, or is OP taking the ninja approach to turning the series into a ki/energy based form of fighting?
What have we got?
Shanks can send sea dragons running off. He can cause hardened grown men to lose consciousness in his presence and destroy matter just from his so-called 'ambition'.
Luffy now seems to be dipping his feet in the water with this ability and Rayleigh can fucking snipe you with it.
Now just a few chapters back we learn that Roger couldn't read the Poneglyph and yet he heard the 'voice of all things'?
I'm starting to get a real Lifestream/ki vibe goin' on here.
I won't suggest we'll see planet destroying energy beams anytime soon, but there's definitely something brewing in Oda Inc.
I'm actually hoping that Oda will go with the Avatar approach with multiple styles of controlling chi and each style having its opposite.
I mean, you can have hard and fast chi usage, but that costs a lot of energy, or you can have soft and slow chi usage, but it conserves and controls energy. Chi can be strong and sturdy, or it can be weak and volatile.
In martial arts, a person who relies on brute force is really easy to beat. All you have to do is use that person's own momentum against him. It's like the lumbering muscular brute is countered by his opposite. A master is able to manipulate his opponents and use any style to defeat them. Chi is studied in martial arts for this exact purpose.
In One Piece, Hawkeyes showed us his power by slicing giant ships into pieces, but he defended against bullets by controlling the path of the bullets in the air. He completely controlled Zoro like an animal with a tiny knife.
I think One Piece revealed Haki as just one type of ki, a forceful one that squashes opponents. The opposite would be a ki that gently moves a person to and fro.
In a way, I think that's why Zoro gets lost so easily, he uses his brutish instincts to move around, but that just makes him controlled by whatever. Nami is the opposite, and takes the cautious sensing of the weather to determine the correct course of action.