Moromitsu is a smith of the late period, and the published sources hand him down in the as the son of Rinko and the father of the Oei- master Morimitsu. Signed and dated survive from the Eiwa, and Shitoku eras through Eitoku and Meitoku, and the references read the present blades as the first generation of the name, a hand earlier than the Oei-dated Moromitsu who carried it on. He belongs to the group of late- smiths the published record collectively calls , the small-curvature makers who worked at the periphery of the great workshop, and the names him plainly as one of its leading hands, 「南北朝後期の、所謂小反り物と呼ばれる刀工達の、代表的な一人である」. The line is recorded as continuing for several generations into the period, but it is this first Moromitsu whose dated anchor the group, the Eitoku piece of 1381 and the Shitoku and Eiwa blades among the few firmly dated witnesses to work just before the Oei flowering.
His characteristic hand is a small-patterned built on a shallow . Into that quiet base he sets , running two by two in sequence, slight and a little , the whole kept small and held down so that the temper, as the published sources put it on his most archaic , lies low across the blade. and enter, the temper is carried in with adhering, and fine run through the pattern, on his best work joined by . The reading the return again and again is one of restraint: his is the subdued register of , 「刃文は盛光、康光に比して地味であり、いわゆる小反りの作域のものである」, a manner more reticent than that of his son Morimitsu and of Yasumitsu, who would temper the idea in the bolder, more decorative pattern of Oei-. The scale itself is the tell. Where the mainstream of the height reaches for height and flourish, Moromitsu compacts everything, the running in small forms that demand to be read closely, and the published sources judge the result, on a dated shortened only a little, 「いかにも師光の持味を発揮した出来の宜しい一口といえよう」.
The is an , often standing and flowing toward the edge, mixed with and on the finest blades forged tight with the grain standing finely. Over it lie , frequent and patches of , and out of that steel rises the , sometimes faint, on his best late a conspicuous , and on one small Eitoku a straight standing clear. The published record reads this as the proof of the - beneath the quiet temper, and on the Meitoku of 1391 it goes further, praising a bright and clear with a blue-black cast, 「青黒い色調に冴えた地鉄が強く、総じて優れた出来の一口である」. The bearing of these blades is archaic. They keep with pronounced , the often thick for the width, and on the oldest the compacts toward an profile, all of which the reads as marks of the late date. The answers the small with a that tends to a pointed tip or settles into a , the very point often brushed with ; many of the carry a , and several add devotional carving, a , a , a cut in grass style at the foot of the groove.
The corpus admits a reading in three registers without straining the evidence. The staple is the subdued small-pattern just described, the work the published sources call the typical manner. A second, narrower register is his most varied, set down on the Shitoku-dated : there the temper opens into mixed with , and pointed elements, a tendency appearing here and there, entering well and the full and rounded, a piece the reads as more varied in range while keeping a high degree of completeness. A third register widens past the norm altogether. On one signed the takes into itself with the valleys opening toward the , and the turns flamboyant. The frames it as the exception that proves the rule, observing first that 「小反り物の作風は総体に小づんだ乱れ刃をあらわすものが一般的である」 and then that this blade instead 「焼きに高低のある華やかな出来口を示しており」, a temper of marked height variation that 「宛ら応永備前を想わせる作風を見せている」. It is on that threshold that the smith is most clearly located, the -mixed and the opening already foreshadowing the work his son would bring to its flowering.
What sets Moromitsu apart is read best from his own blades rather than by contrast. His bright over standing , his small-pattern carrying and slight , and his place him squarely in the -, while the smallness and restraint of the whole separate him from the mainstream of the height and from his own bolder successors. The published sources weave his lineage into nearly every entry, the giving him as 「銘鑑に倫光子、盛光の父とあり」, son of Rinko and father of Morimitsu, and they place him at the hinge of the school's history, the last quiet phase of and the first intimation of Oei- carried in a single hand. The faint dating spread of his signed works, Eiwa through Meitoku in the present blades and on to Oei in the references, gives the group its chronological spine, so that his blades serve the study of the period as much as the eye.
Moromitsu survives almost entirely as signed and dated , and seven of his blades carry the designation; he holds no National Treasure or Important Cultural Property, so his record runs through the tier rather than the patrimony preserved in museums and shrines. Fujishiro rates him Jo-. The value of the surviving work lies as much in its documentary weight as in its beauty: , signed, dated blades are read in entry after entry as fine reference material for the group and for the smiths standing at the threshold of Oei, the rare Eitoku and Shitoku dates singled out as precious, the calling the Shitoku 「とりわけ至徳年紀が貴重な同工の優品である」. Provenance is thin and worth stating plainly: of the recorded whereabouts, one of his finest , sound in , and , is an old treasured piece of the Shonai Sakai family, 「庄内酒井家の旧蔵品である」. For a private collector the Moromitsu is not beyond reach in the way a National Treasure is, his designated work sitting in the tier rather than locked in public hands, yet a signed and dated by the first-generation hand comes to market only rarely, a quiet landmark of late- when it does.