I always keep enough pressure on the spine to avoid picking it up off of the stropping surface. The edge lightly skims the surface. I've stropped on all the usual leathers, poly webbing, racing harness salvaged from a nascar vehicle given to me by a mechanic, wool felt, newspaper. I've never chipped an edge stropping yet. Not saying it can't happen or didn't happen, just that it is beyond my realm of experience.