I would say there's only one, and that is, shaving with it. Even then, it will depend on the feeling/result ratio.
What do I mean by this? Well, this morning I honed a Robert Kelly "Kelson" razor, English, pre 1892. I was quite happy with the way it was behaving on the stones, and it did shave the hairs on my arm pretty effortlessly. It didn't treetop, however, which is something that didn't leave me all that happy. After stropping, HHT was nowhere to be found, it wouldn't cut a hair for its life.
However, knowing that something HHT means nothing, I gave it a go. WTG, there was a bit of pulling (the "feeling" part in the ratio I was talking about earlier), but nothing unbearable, just that "hmmm-I've-seen-better" feeling. Finish, rinse, check, fairly good WTG, promising. ATG, no problems, even fool's pass, despite not being 100% effortless, it was good.
The end result was an absolutely delightful GBS
, one I could be 98%+ happy.
Granted, someone with a lesser technique, or someone who doesn't know his own face and needs as well as I do, might perhaps struggle a bit more, but I ultimately don't think there's a standard for sharpness. I know people who swear by the HHT, and that would have not even dared to put this razor against their whiskers, just because of it. However, it worked flawlessly for me. Go figure.
What do I mean by this? Well, this morning I honed a Robert Kelly "Kelson" razor, English, pre 1892. I was quite happy with the way it was behaving on the stones, and it did shave the hairs on my arm pretty effortlessly. It didn't treetop, however, which is something that didn't leave me all that happy. After stropping, HHT was nowhere to be found, it wouldn't cut a hair for its life.
However, knowing that something HHT means nothing, I gave it a go. WTG, there was a bit of pulling (the "feeling" part in the ratio I was talking about earlier), but nothing unbearable, just that "hmmm-I've-seen-better" feeling. Finish, rinse, check, fairly good WTG, promising. ATG, no problems, even fool's pass, despite not being 100% effortless, it was good.
The end result was an absolutely delightful GBS

Granted, someone with a lesser technique, or someone who doesn't know his own face and needs as well as I do, might perhaps struggle a bit more, but I ultimately don't think there's a standard for sharpness. I know people who swear by the HHT, and that would have not even dared to put this razor against their whiskers, just because of it. However, it worked flawlessly for me. Go figure.