On a of Eisho 9 (1512), beneath the long signature of Jirozaemon-no-jo Fujiwara Katsumitsu, the smith added a phrase of his own: "as far as my heart can reach, nothing could surpass this", declaring the blade a work that fully satisfied him. The maker of that boast is the most accomplished bearer of a crowded name. The published sources record that several generations and more than a dozen smiths used the name Katsumitsu among the late- forges collectively called , and that within that crowd the branch titled Jirozaemon-no-jo, the son of Ukyo-no- Katsumitsu, is especially accomplished, counted with Yosozaemon-no-jo Sukesada and Gorozaemon-no-jo Kiyomitsu as a representative smith of the late tradition.
What the published sources name as his individuality is a matter of degree within a shared idiom. Every smith tempers the open-waisted, double-structured , the - that is the diagnostic late- line; Katsumitsu builds his prime on the same base, well-packed carrying and fine , over which the temper rides high and bright with and entering richly, the clear and tightening, small interspersed. The distinction the judges draw is that he mixes into that more freely than his fellows, for a more flamboyant effect. "Compared with Sukesada," the sources write, "Katsumitsu shows more conspicuous in the temper, and the so-called crab-claw (kani-no-) irregularities appear relatively less often". On his finest dated the same point is put positively: he is "particularly adept at a more splendid workmanship in which abundant are intermingled within the ".
The is the constant beneath that flamboyance. It is the well-packed of late , attaching, finely woven, in places a little standing or flowing; on the best pieces the lies fine as dust ( michin). The classical of old has largely gone from this late steel and appears only faintly on a few blades; one Eisho-2 is read as showing little precisely because the is so strong, so that the itself looks powerful. The answers the , running to a or a pointed tendency, at the tip and a turnback. Across both faces lie the devotional carvings of , a , with , and shrine names such as and Amaterasu Kotaijin, which the sources are careful to call the work of collaborating horimonoshi rather than the smith's own hand.
Katsumitsu is the most frequent collaborator of the house, and a large part of his record is joint work. With his brother Sakyo-no- Munemitsu he cut the blades long prized as , the two names signed together on katate-uchi and ; on one Eisho-7 the inscription explicitly reads "younger brother, Sakyo-no- Munemitsu", a line the sources call extremely important material urging a reexamination of the genealogy. The single most celebrated work is the joint with Yosozaemon-no-jo Sukesada, dated Eisho 18, a bold and magnificent with the incised inscriptions Hagun-no- and Sanshin-soku-ittai, commissioned by Ukita Yoshie and called "a masterpiece among ". A of Daiei 3 is a joint work with his son Jirobei-no-jo Harumitsu. One entry places his working span roughly from the Meio into the Kyoroku era, another from Chokyo into Tenbun. Late in that span, dated Kyoroku 2, he forged a father-and-son joint with another son, Shuri-no- Katsumitsu. Its temper is deep, as on the work of Yosozaemon-no-jo Sukesada, the loose and the lower half breaking into large ; the sources call it a blade to be taken as typical of work and the father-and-son signature valuable as documentation. Beside the flamboyant he tempers a calm, broad and with equal command, the sources observing that the master famed for flamboyant through the Asa-arashi shows, with his uncle's help, an advanced skill even in a straight temper. A dated Entoku 2 (1490), signed Jirozaemon Katsumitsu, carries a over a cleanly packed , and working well and a strongly shining that in places spills into the ; the sources note that besides his usual work he is skilled at such a straight temper too. A of Meio 8 (1499) takes the very thick, narrowing form, its temper a -based with frayed edges, and , which the sources judge an excellent piece of work.
What sets Katsumitsu apart within his own school is therefore the reach of his hand rather than a single tell. His bright, -mixed distinguishes his prime from the plainer Sukesada manner, while his command of a clear and his ambition outside the standard idiom mark the upper edge of late- workmanship. The clearest sign of that ambition is a signed Bunki-2 , slender with , that abandons the contemporary for a -based with over a in which a rises; it is read as "a piece conceived with the late- of Kagemitsu and his fellows as its aim", an unusually forceful work, though the sources add that its technique does not reach its model. At the far edge a Daiei-6 carries the temper up the into a -like with , more varied than usual. These outliers map the breadth across which the Katsumitsu hand can be known.
Katsumitsu was a productive smith and signed and dated work survives in fair number, yet little of it can ever change hands. Fujishiro grades him Sai-jo . He has no National Treasures; his record runs instead through one Important Cultural Property, the joint with his son Harumitsu held at Nogi Shrine in Tokyo and inscribed Ichigo-ikkoshi, and through three blades recorded in Honma's inventory of the Imperial collection: a and a signed Bishu Katsumitsu with Eisho dates, and a signed jointly with his brother Sakyo-no- Munemitsu. The patrimony continues in the houses and old collections grounded in their own provenance, the joint for Ukita Yoshie a treasured heirloom of the Sendai Date family, other blades recording owners such as Uyama Hida-no-kami and Kitamura Yukinao, the Jubi Asa-arashi once held by Matsushita Masatoshi. Beyond these, of the twenty-nine designated works on record, twenty-four sit in the and tiers. Most of them are held rather than traded, so a signed Jirozaemon-no-jo Katsumitsu comes to market only from time to time, and a dated, devotionally carved example, the kind on which the smith once wrote that nothing could surpass it, is a rewarding thing for a collector of late to encounter.