Brian: Perhaps you have never learned how to use a sharp knife safely. You cut away from your body, and anything else you don't want to cut.
To cut the patch at the muzzle, you first seat the ball below the muzzle, in the patch. Then you pull up on the edges of the patch, and use a very sharp knife, starting closest to your body, and cutting away from it, to cut the cloth patch off even with the muzzle. If you are grasping the cloth completely in the fingers of your other( left) hand, The blade should pass safely under your thumb and forefinger, and cut the cloth with one stroke.
Many buckskinners use a straight razor mounted in a handle- often antler-- to serve as a patch cutter. There is no need for a point on the cutter, like you would expect to find on a knife.
A flat, straight edge is what serves the purpose best of all. Straight razors can be ground on the right side of the blade only, for right handed shooters, thereby leaving the left side a flat edge like a chisel, which will lay flat on the muzzle as you cut the patch. With the bevel on the top, the bevel will tend to force the edge to remain against the barrel as you cut.
These knifes and razors are usually kept razor sharp. You need both a fine abrasive, and a strop to keep the blade sharp, and free of burrs.With a single bevel blade, you can use fine emery paper glued to a good flat hardwood board for sharpening. For a strop, you can make good use of any old belt. To sharpen, move the edge Towards the abrasive, as if you were slicing off a thin layer. For Stropping, draw the blade back away from the edge, and work both sides, so that the micro burrs that are raised during sharpening are removed, and the edge polished. Properly sharpened, the edge will cut the cloth without any real pressure.
You don't want to use a dull knife to cut patches, as the dull edge will require you to use your Large Muscles, and that is how you can lose control of the blade and cut something or someone you didn't intend to cut. A good clue that a knife is dull is when you see the owner using it on cloth as if he had a saw blade, moving it back and forth to cut.
A fine, sharp edge cuts with the use of your fine coordination muscles, so that you are always in control. You will see the owner cut the patch with one or two strokes, depending on the size of the patching and caliber of his gun.