He had a revolutionary idea, in those days, of spectacularly improving the defensive power of a castle in the tamonyagura (hall turret) that combined the castle gate with a turret, which we take for granted, having seen many existent castle buildings.
現存する城郭建築を見ている現代の我々はさほど驚かないが、多聞櫓における城門と櫓を一体化させ防御力を飛躍的に向上させるという発想は、当時においてまさに革命的であった。