We use the same words with different meanings.
I would like to distinguish between slashing and hacking, or chopping.
The #1 has an unsharpened spine which increases the mass of the blade and thereby its momentum.
The #1 hacks or chops better than the #2 because of its increased momentum.
However, the same mass which creates momentum also creates inertia, meaning the #1 does not change directions as quickly as the #2.
Yes, the metal removed in the clip of all bowie types of knives, the #1 included, lightens the tip and restores some of the quickness of the blade lost to the thick unsharpened spine, but not all of it.
I tend to entertain the speculation that Jim Bowie might have held his knife edge-up, with the clip down.
This allowed him to use the clip in a hacking movement with great force, the unsharpened spine as a club, and the sharpened upper edge for the reverse draw cut.
An edge-up grip makes much better use of all of the sharpened edges and the point than does our modern conventional way of holding a clip-point fighting-knife with its edge down, because edge-up preserves both the reverse draw cut and the forward hack or chop; however, it also sacrifices the forward draw cut.
The double-edged fighting dagger, and by that I mean a #2 with an 8" blade, will slash forwards and backwards, and it will draw cut forward and backwards (the Arkansas Toothpick, which has some of the form of a double edged dagger but lacks it fullness, will not draw cut as well as the #2).
Because of the mass removed from the spine in order to sharpen the second edge, the double-edged dagger loses a significant amount of momentum in the hack but it also loses the same amount of inertia; a loss of inertia which allows it greater acceleration and quickness when it comes to changing directions.
The double-edged dagger will still do a whip-cut, although not with the force of a #1.
More importantly the #2 will slash with great effectiveness when applied with a strong wrist and a coordinated movement of the shoulder and upper and lower arm.
Additionally, the double-edged dagger resolves both the wrist grab and the question of whether to hold the knife edge-in or edge-out when using the reverse grip.
Finally, yes, finally, I repeat for emphasis that in a survival situation the double-edged knife has twice the number of inches of sharpened edge, or, in essence, two knives on one handle.
The double-edged dagger will last TWICE as long and cut twice as many manila ropes and cardboard boxes as will a single-edged bowie type of knife.
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