Tadamitsu is, with Katsumitsu and Munemitsu, one of the representative smiths of the late- forges collectively called . The name itself is old, and the signature compendia place a first generation as far back as the Shoo or Genko eras and count several generations down through Eiroku and Tensho; of those earliest masters no work survives, the oldest examined blade being a Joji-dated piece. The Tadamitsu who is widely known, and whose dated and signed swords fill almost the whole of the surviving record, is the smith bearing the common name Hikobei-jo, working in the Bunmei, Entoku and Meio years (1469 to 1501). The published sources rank him directly: "alongside Katsumitsu and Munemitsu, Tadamitsu is counted among the representative smiths of ," and, among the several smiths signing the name, "the Tadamitsu who took the title Hikobei-jo is the most accomplished".
What the published sources name as his individuality is one quality above all: within a school otherwise defined by its flamboyant clove-and- temper, he is the master of the straight edge. They call him plainly "the master of among the smiths", and the reputation recurs across his entries down the decades. His characteristic blade tempers a , at times a broad shallowly , the tight and bright, adhering, small and worked into the edge, with and a little ; the runs straight into a , now and then tempered down rather long. It is a quiet, exacting temper, and it is what a collector reads first in his hand.
The quality that carries that quiet temper is the steel beneath it. His is a well-packed with and , standing a little in places, and the judges return to its cleanness again and again, calling it in two separate entries "a that is exceedingly clean". On the broader of his larger blades a faint or, on the showiest, a rises in the . Within he had long been held especially accomplished in forging, the published commentary says, and that refinement of the is the constant on which both his tempers rest.
His is not a one-manner hand, and the second register is the inherently . "Many of Tadamitsu's best works are skillful ," the sources allow, "yet here he has tempered a -ba, and in doing so does not fall behind Katsumitsu and Munemitsu" (忠光には直刃の上手な作品が多い … 備前本来の乱れ刃もまた得意). On these he sets an open-waisted mixed with and , and entering freely, adhering, with , and the occasional , the running to a small round or a pointed return. He works almost wholly in the late- idiom, the compact katate-uchi with and a short tang, made, as one entry observes, "to suit one-handed draw-cutting", and his blades carry on both faces the devotional carvings, a grass , , and the shrine name . He is also counted, beside Norimitsu, among the few makers of fine spears, his and omi- well refined in a flowing .
What sets the Hikobei-jo Tadamitsu apart, then, is named by the judges from within his own work rather than borrowed from a comparison. Where his contemporaries Katsumitsu and Munemitsu are read through the flamboyant and the open-waisted clove temper, Tadamitsu is read through the bright, tight and the clean that the sources praise as the sign of a superior forger; and when he does turn to the , it is the inherently line, the equal of his peers'. He stands, with them, at the head of late , and several of his blades are joint works with other smiths bearing the name, one with Hikosaburo "whose personal name is clearly Tadamitsu," another with Kurozaemon, the circumstance of two Tadamitsu smiths signing a single blade together called particularly intriguing. One Entoku 2 even records that he forged on assignment at Iioka-go in Sakushu, a smith working across the provincial border in Mimasaka.
For the collector he is an unusually knowable name, and an attainable one. Fujishiro grades him Jo-jo . He has no National Treasures and no Important Cultural Properties; his standing rests instead on twenty-two blades on record in the tier, spanning , , , and omi- and a wide span of dated years, with three signed preserved in the Imperial collection and one cut with a Yamano Nagahisa gold-inlaid cutting-test inscription. Provenance is recorded for only a handful, among them the Imperial Household and the named owners Ide Tokuichi and the commissioner Watanabe Shinzaemon. Because so few of his blades carry locked designations, a signed and dated Tadamitsu is among the more findable of the great names; one comes to market from time to time, and a example, almost always signed and very often dated to the year, is a document of late at the height of its craft, a sword whose maker and month can be read directly off the tang.