Probably because of the necessity for working in the battlefield, Moritomo's father, Daizen Moriyoshi, independently developed a technique of 'shito (sword trying)' to determine the performance of a sword and taught it to Moritomo.
父大膳衛好は戦場働きの必然性のためか、刀剣の性能を見極める「試刀」の技術を独自に編み出して衛友に伝授した。