No need to apologize, I didn't post it to start an arguement. Mostly it was to share information. Dan's doesn't just sell them, my understanding is they also own one of the mines in which these hones are quarried from. So I would like to believe they're being forthright in their information.
As to yours in particular, if they both came from the same seller, and the translucent is good quality then I'm sure they sold you the black in good faith as well. And I don't doubt that yours behave as you say they do.
I apologize if my post came off as combative, defensive, or worse - derogatory. Such was not my intent. Mostly the post was made to point out that there are a variety of Black Arkansas stones in grades above and below Translucent stones, and that one must be careful to find a reputable dealer - as it sounds like you did.
In my own search (I'm constantly on the lookout for these) I've seen hones called 'surgical black' at hard Arkansas hone prices. These are the ones I am particularly wary and suspicious of.
I agree with you that sharpening these blades is quite a challenge. Much more so than shaving with them, learning that was the easy part.
I've got one of those stone wheels you speak of. It belonged to my grandfather, and I'm sure came from his father before him. I've never thought to use it on anything, the stone itself seems rather coarse and badly worn from misuse.