The hasaki under the yokotesuji was not entirely sharpened before. Because we make the real geometry yokotesuji. This case is normal amoun the mass-produced sword. It won’t happen if it’s not real geomitry yokotesuji. Now we have solved this problem. However with the increase in cost.
We can’t make a true geometric hasaki When the kissaki is oversized. Unless we increase the thickness of the saki-kasane. But that would influence the balance of the sword