Who said this is a "fact"?? Where are you getting this fact from? State your source because it is incorrect. On a hollow grind, the flat piece at the end of the hollow grind is not wider than the cut so there cant be any more resistance than what a full flat grind can create. In fact, the resistance as the material slides up the sides of a the blade is more on a full flat grind because this resistance is always present through the entire cut across the blade. Lets not forget slicing doesn't have to go through the entire blade stock to begin with. This is why a hollow ground will slice better because it is simply a thinner piece of steel doing the work. I believe blade geometry doesnt lie and thats why it supports my point of view. I also agree that, all things being equal, a coated blade will have a minute more amount of friction than a non coated blade.
Actually, this is an incorrect statement. Hollow ground knives do not slice better than full flat ground knives. You get to a point on a hollow ground knife where the grind is not there anymore and you know have a flat piece of blade to deal with that offers resistance. Flat ground blades slice better because they are flat all the way up to the spine and do not offer resistance due to the flat piece of blade.
Blade geometry does not lie. Fact is fact.
Here is 2 minutes of research on this that supports why a hollow ground always slices better:
Hollow Grind:
The blade made with this grind is essentially "scooped" out each side, leaving a thin but very sharp edge.
This grind really shines when it comes to slicing and can be made to slice/slash at high performance levels. The hollow grind is not necessarily the best for impact, chopping or hard outdoor use such as a camp knife might see. The thin edge which gives it the sharp slicing ability also makes it weak for these harder use chores.
Flat Grind or Taper Grind:
The flat grind is a continuous bevel beginning at the spine of the blade and continuing evenly through the width of the blade to the edge. The thickness of the blade decreases as the bevel nears the edge, but the decrease is linear and flat as opposed to the hollow grind which makes a concave surface on the blade. The flat grind is basically "in between" the convex grind and hollow grind. It does incorporate some of the best characteristics of each. The edge can be made quite sharp, like the hollow grind, but is also more resilient to higher levels of impact, like the convex grind.
The flat grind can be outdone on each end of the spectrum by the hollow and convex grinds, but as a general use grind to handle everything, the flat grind is an excellent choice.
From Masters knife maker Jay Fisher:
Any knife grind that creates a thin enough edge can be made sharp, and can be made to cut various materials. The shape of the blade does matter when it comes to cutting friction, and resistance while the knife blade is deep in the cut. Just what grind has the least and most resistance to cutting friction on the sides of the blade?
I read a comment once where the writer had claimed the convex grind or rolled edge has less friction because it only contacts on a tangential point. This would be true if only the material being cut has no give, no movement, no springiness to it. Also, as that material is cut, it would just open up, not pinch, but contact rigidly at one single point. But just what material would that be?
The fact that you are cutting instead of sawing means that you are not removing any material from the cut. In a saw cut, the teeth on the blade have a wider kerf than the blade itself, so that is why the saw blade does not stick and create friction in the cut. Knife blades have no kerf, no material is removed in the cutting action, so the material being cut will, of course, try to fill the cut, and push against the sides of the blade.
The thinner the blade, the less friction and resistance. A taper or convex grind or rolled edge will push outward on the material being cut at a greater amount than any other knife grind cross sectional geometry. A flat grind will press less, and a hollow grind offers the thinnest blade and the least friction of any blade grind. This may seem like a small item, but in combat knives, where great force is delivered to the blade edge, and tough fibers, textiles, and tissue create great friction in the cut, any advantage is welcome. This is another reason nearly every military combat professional that I make CQC and CQB knives for requests hollow ground blades, whether the knife is straight, swept, or recurve in profile.
