Tosa no Kami Tadayoshi occupies a position of singular ambiguity within the Hizen tradition. The NBTHK setsumei observe that "there are many competing theories, and it remains uncertain who he actually was," though "there is no doubt that he stood in a very close relationship to the first-generation Tadayoshi." It is transmitted that when the first-generation Tadayoshi changed his name to Tadahiro in Kan'ei 1 (1624), the Tadayoshi signature was transferred to this smith, who subsequently received the court titles Tosa no Jo and then Tosa no Kami. The third-generation Mutsu no Kami Tadayoshi, the legitimate heir of the second-generation Omi no Daijo Tadahiro, predeceased his father, and surviving works by both Tosa no Kami and Mutsu no Kami are comparatively rare.

Across extant designations, the hallmarks of the Hizen school are consistently evident. The kitae ranges from tightly forged ko-itame-hada with well-adhering ji-nie to dense ko-itame of fine quality. The hamon encompasses both spirited midare-ba -- including choji mixed with gunome and ko-gunome, with deep nioi and well-adhering ko-nie and sunagashi -- and the vigorous choji-midare with intermingled tobiyaki characteristic of the school's more animated works. Blades attributed before the receipt of the Tosa title display particularly fine workmanship, with the jigane described as "well-forged and tightly refined."

The setsumei emphasize both the rarity and the scholarly value of these works. The Kan'ei 1 dated blade is described as "extremely valuable material for the study of Hizen swords," as it sits at the precise moment of the name transfer from first-generation to successor. Among the broader Hizen tradition, naginata by any generation are noted as "few in number," lending additional significance to the third-generation's contribution in that form. Across all attributions, the consistent refinement of both ji and ha affirms the intimate continuity linking these smiths to the founding standards of the Hizen school.

Tosa no Kami Tadayoshi occupies a position of singular ambiguity within the Hizen tradition. The NBTHK setsumei observe that "there are many competing theories, and it remains uncertain who he actually was," though "there is no doubt that he stood in a very close relationship to the first-generation Tadayoshi." It is transmitted that when the first-generation Tadayoshi changed his name to Tadahiro in Kan'ei 1 (1624), the Tadayoshi signature was transferred to this smith, who subsequently received the court titles Tosa no Jo and then Tosa no Kami. The third-generation Mutsu no Kami Tadayoshi, the legitimate heir of the second-generation Omi no Daijo Tadahiro, predeceased his father, and surviving works by both Tosa no Kami and Mutsu no Kami are comparatively rare.

Across extant designations, the hallmarks of the Hizen school are consistently evident. The kitae ranges from tightly forged ko-itame-hada with well-adhering ji-nie to dense ko-itame of fine quality. The hamon encompasses both spirited midare-ba -- including choji mixed with gunome and ko-gunome, with deep nioi and well-adhering ko-nie and sunagashi -- and the vigorous choji-midare with intermingled tobiyaki characteristic of the school's more animated works. Blades attributed before the receipt of the Tosa title display particularly fine workmanship, with the jigane described as "well-forged and tightly refined."

The setsumei emphasize both the rarity and the scholarly value of these works. The Kan'ei 1 dated blade is described as "extremely valuable material for the study of Hizen swords," as it sits at the precise moment of the name transfer from first-generation to successor. Among the broader Hizen tradition, naginata by any generation are noted as "few in number," lending additional significance to the third-generation's contribution in that form. Across all attributions, the consistent refinement of both ji and ha affirms the intimate continuity linking these smiths to the founding standards of the Hizen school.