Natichu

While I (unsurprisingly) have no insights to share, I for one would love to see more pictures of the rest of the sword if you're willing to share!

While I haven't seen this "study" you're referencing, I'm not sure your conclusions follow or derision makes any sense, at least from your description of it. Do you have a link or source setting out the methodology? More generally, any list of top wines is one person or panel's subjective opinions, and one wouldn't expect a different person or panel to reproduce it. It's not some list with objectively gradiating features that distinguish one from the other in terms of "quality" when clearly they are all good wines. This is why people into wine read reviews and rankings lists written by multiple people and learn to understand the tastes and preferences of the reviewers and how they match up with their own. The question I would have thought more pertinent would be whether the experts (who I'll assume were sommeliers, not just connoisseurs) could identify the wines, not order them based on the results of someone else's rankings. This isn't to say there isn't plenty of bunk in the wine world, but I'm not sure whatever it is you've identified here counts for much. Regardless, back to swords, and while I certainly can't speak to any requirements of assessors, nyusatsu kantei is very much a thing and one would imagine something they participate in regularly. It might be worth your checking out the regular kantei problems posted by the NBTHK (latest here: https://www.touken.or.jp/english/nbthk/swordjournal_December.html) and referencing some of the usual books on the process.

Useful article here from Markus Sesko on Tensho vs Keicho suriage: https://markussesko.com/2018/04/25/tensho-suriage-and-keicho-suriage/

Very interesting, first as I've been pining after a Nobutaka wakizashi in Eirakudo (https://eirakudo.shop/601981), but also as it reminds me of one of the recent NBTHK kantei problems available on their website. I again thought Nanbokucho Mino and in my head guessed Naoe, whereas the correct answer was Horikawa Kunihiro. While I don't know that I can do a translation any justice, the initial discussion on the sugata points to viable options as Nanbokucho, Keicho Shinto (and very late Muromachi), and Shinshinto. It then goes on to discuss why the first and last options didn't fit the bill. Problem and solution images below:

Just for example on that point, you have this on Touken Komachi as well (quite a nice sword to my eye, but with a few knocks against being likely shinshinto suriage and mumei): https://www.toukenkomachi.com/index_ja_tachi&katanaA021125.html Kurashiki papers to a jojo-saku ranked smith, and then four months later NBTHK papers Hozon to...Takada. Not to knock Takada (I have a lot of interest in the school) but that seems like a pretty significant downgrade.

Thanks for this Jussi. Just in terms of showing my thought process (primarily so that my beginner mistakes can be highlighted for me) to my eye Nanbokucho sugata, with the size and o-suriage pointing to that period rather than a retro throwback from a later period. Masame/nagare in the shinogi-ji pointing to Mino-den, and togari elements in the hamon agreeing with that. Guess is Naoe Shizu (maybe Kanetomo or Kanenobu?).

I may have something that fits the bill that I'm debating parting with. Am tied up for the next few days but want to shoot me a PM? Hozon, late Muromachi, shobu zukuri. Otherwise there are a few good options (at least to my beginner mind) in the for sale section here on NMB. Would also recommend checking out Touken Komachi as Tsukada-san is great to work with and she has quite a few reasonably priced offerings: https://www.toukenkomachi.com/index_en_tachi&katana.html

Is the mei signed over top of the patina/corrosion on the nakago?

For reference, some of the security features of the Hozon and Tokubetsu Hozon papers are discussed here: https://www.nihontocraft.com/japanese_sword_papers.html

My apologies for the quote Rohan, but I can't get the spoiler box to work on my phone. Have edited the contents of the spoiler box (so its content is mine, not Rohan's), though conveniently I agree with Rohan's order.

My understanding was that the NBTHK only specifies generations in rather rare cases (or I suppose better put, typically does not specify generation). Am I incorrect in this, or is there a peculiar exception for this school?

Now that is quite the stunning piece. Not to sidetrack from the original topic too much, but would you mind posting the measurements of the Sukesada?

Very interested to see what the more experienced members think, but just on their face they seem quite different pieces, while both gorgeous. A large and wide Enbun-Joji sugata Yamato style katana vs a rather elegant katateuchi-seeming Bizen blade (at least to my beginner eye, given its short length, narrow width, and shorter nakago). I like them both, but would enjoy hearing what draws you to each of them.

Phenomenal, thank you very much! That is extremely helpful and greatly appreciated.

Hi Michael, Yes, it should be Hoki Province with work in the Shinshinto period (Ansei era ish), and one of the smith's names was indeed Shimizu Yoshiyuki (apparently after being adopted by another swordsmith it seems). I think you have found him there.