I like the DMT diamond sharpening rod. No oil no water and it does grooves because it tapers to a point. It’s very light weight. Occasionally out of some kind of stupidity on my part I get a cut. Usually nothing that can’t be handled by the superglue in my first aid kit. Knives are made out of so many different types of steel, it’s fascinating to see what can be sharpened easily and what can’t be. Sometimes I think the only knife I should carry is a box cutter with a bimetallic blade. Gets dull just flip and keep going.