Nothing will ever replace studying a sword in hands; it is the one and only way to appreciate all its subtleties. Even the swords on display in museums cannot be studied fully and seriously. Everything else is just hot air.
Although Sukehiro's signature style has evolved over time, there are certain constants, especially in the kaisho style. Unfortunately, this blade is gimei.
Never forget that polishing a sword is never harmless, it accelerates wear and tear and can reveal a flaw that might reduce its value. From what I can see, this sword has already been polished many times. It is therefore worth considering whether it needs to be polished again.
It's why i said good luck. But some people here think they can determine the origin of a sword (said Gimei ) based on a few poor-quality photos.
As for me, despite all my experience, I've never managed to do it.
There is a misunderstanding regarding the difference in quality between Koto-period swords (particularly those from the Kamakura and Nanbokucho periods) and swords from other eras. Practicality is not the issue; a sword is a lethal weapon, and a kazu-uchi mono gets the job done. The difference lies in the artistic qualities of these swords.
That's what I did for many years
Joy, yes. For knowledge, it depends on what you mean by that word. I don't think we have the same understanding of that word.