There was an instance where Yasuhiro NISHIGAYA positioned the Uto-yagura turret of Kumamoto-jo Castle and the Daidokoro-yagura turret and Koran-yagura turret of Ozu-jo Castle as sho-tenshu (small keeps), thereby designating these turrets the existing castle towers.
また、西ヶ谷恭弘のように熊本城宇土櫓と大洲城台所櫓・高欄櫓を小天守と位置づけて現存天守とすることもある。