Chisel edge on Filipino Blades

[KuKulzA28]

While some might differ, I know with the laraw (Taiwanese aboriginal headhunting/survival knife of the Atayal group) I have handled, their single-bevel blades are kind of like what migueldiaz is saying...

Here's a diagram I made. The flat side is angled to make the edge centered instead of to the side so to speak. Where-as others are to the side and others have a double bevel.