Edge 1:

The importance of the edge relates to how bad one will get cut. Some edges are fine, as others thick. Awarness of double edges or single edges.

The types of cuts generated by these different edges should be examined. Why?? to understand which parts of the body can be safely used in a denfense situation.

Types of steel control the outcome of how sharp the edge will be. It is a bit harder to determine the exact steel used but also vital.

Stainless blades are harder to sharpen and edge are often not razor sharp. As the chrom increases in the making of stainless the carbon decreases. They quickly loose the their edges.

Knowledge of the blade extends for beyond the block.

Kobun