About 20 years ago they should have created a grading standard for chalk so they could have avoided their commoditization, or at least only compete with others at similar quality (and presumably margins). Similar to organic standards.
Yes, this is what I wanted to say. Quantify what makes them great. After reading the article and the comments, I still have no understanding of why or what makes them so great.
Basically, the chalk seems to be optimized for writing Kanji strokes which need to vary in thickness and weight.
And, yes, he did miss the boat in the US. I have never heard of this stuff before they went under (not completely true: my Japanese teacher complained about the quality of American chalk all the time--I should have twigged in). I would have bought crates of this stuff when I was teaching.
Hopefully the Korean company he sold the machines to won't be quite so insular.