What if Rokushiki is Haki based?

In One Piece, why do the members of CP9 learn to use the “six powers”, but not haki? - Quora

ROKUSHIKI ACTUALLY HAKI POWER- Yaps, - Mugiwara Dangers

What if Luffy has secret Haki from a descendant Haki Master or Supreme King? - Quora

one piece - What skills introduced prior to the formal introduction of Haki are Busoshoku Haki based? - Anime & Manga Stack Exchange

Which do you prefer in One Piece, Devil Fruit, Haki or Rokushiki? - Quora

What is Conqueror's Haki? What would happen if Luffy had awakened it before his battle with Kaido? - Quora

5 One Piece characters Rob Lucci can beat (and 5 he can't)

One Piece: Rokushiki Explained - How Strong Was Rob Lucci & CP9? (The Six Powers)

Rokushiki Robin UPDATE 12-31-16 (See below) by Shinjojin on DeviantArt

Rob Lucci's initial Vivre Card has been changed from Learned Haki to strengthened Haki related to Rokushiki : r/OnePiece

Rokushiki is based on physical strength is actually based on a mistranslation in earlier One Piece volumes : r/OnePiece

Rob Lucci's initial Vivre Card has been changed from Learned Haki to strengthened Haki related to Rokushiki : r/OnePiece