Question: I've heard that a sharper edge is actually stronger than a dull edge? How can this be?

Answer: There are a couple of good reasons why a dull edge is more prone to damage and dulling than a finely sharpened edge.

A dull edge requires greater cutting force. Greater cutting force tends to dull the edge. In a kitchen, a dull knife is often forced into the food and into the cutting board with great force. With woodworking cutting tools, a dull tool generates a lot of heat when cutting. If the tool becomes too hot it will lose its temper and the cutting edge will become soft and dull almost instantly.

A finely sharpened edge is a highly polished and uniform edge. This uniform edge provides greater strength because the cutting surface doesn't have peaks and valleys that can easily get worn down. This is sometimes hard to visualize so I like to think of an edge of a newly built road. A new road is very smooth and looks new for quite a while. However, old roads with cracks and chips seem to deteriorate rather quickly. A sharp edge is like the newly built road, if cared for properly, it can last a long time.