Hand Tools Archive
Wiley Horne--So. Calif.
Yeah, I understand all that, just as you do. However, I wouldn't trust the ad blurb. It's not specific--who knows what 'high carbon' means to an ad copy writer. There's a language barrier to jump, and Mujingfang is known to use HSS on numerous other irons.
It's worth a check with someone who knows, IMO, if one cares. Someone who has standardized on Arkansas stones would care.