I assume that Iwasaki primarily used a sequence of nagura on a very hard finishing stone. In that system, any edge conditions you have at the finishing stages are difficult to deal with because the abrasive on the stone surface and in a finishing nagura is so small that only a tiny amount of material is removed with each stroke. So, it will take a lot of strokes to clean edge anomalies under those conditions. There are other ways to accomplish burr removal and wire-edge removal. Iwaski’s method seemed valid to me. As I mentioned before, it is not what I do normally.