well the JNS 400 is ok fast.. i did not make some super insane thinning just a bit of correction and some attempt to make something shinogi line like again.
if i want to make a knife thin, i send it to juergen schanz in germany ( i wrecked one 220 shapton glassstone on one single knife before, so i am not crazy )
Oh I didn't just remove the shoulder. I moved the shinogi up to keep the bevel continuous for hamaguri keeping the "shoulder" or shinogi line crisp while reducing wedging.