A harvesting header for a row crop machine has a plurality of row units having fore-and-aft extending arms forming a passageway, a gathering mechanism to gather stalks into the passageway, snap rolls to pull the stalks downwardly through the passageway, and a knife set to cut the stalks in the passageway. The knife set includes a pair of opposing blades, each blade having a main portion with an inner edge located on a first side of a centerline of the passageway and a cutting protrusion with a sharpened cutting edge extending across the centerline toward the opposing blade. The cutting protrusions are offset longitudinally from one another such that the cutting protrusion of one of the blades is a different distance from a mouth of the passageway than the cutting protrusion of the opposing blade such that there is a continuous gap between the blades along the length of blades.
