Dan, I agree with you in every way about Jon's diamond stones except one, recommending these stones to a new sharpener.
I have the Jon's diamond stones, but the cut so aggressively that, Maggie will chew up her knives in short order. I don't think Jon would recommend them either. Maggie should consider a Gesshin two sided soaking stone maybe a 1/6K combo. That way she can learn how to hold the knife on the stones with much less cutting speed that a Diamond stone. Just my thoughts...
I have the Jon's diamond stones, but the cut so aggressively that, Maggie will chew up her knives in short order. I don't think Jon would recommend them either. Maggie should consider a Gesshin two sided soaking stone maybe a 1/6K combo. That way she can learn how to hold the knife on the stones with much less cutting speed that a Diamond stone. Just my thoughts...