I spent a little time puzzling over this particular line in the official PTR Notes.
So I asked myself, what classic weapons are there that aren't still available? Ones that that it would be appropriate for a Blacksmith to forge, as opposed to current sources like the DMF or BMAH? And it struck me that some of the most iconic yet currently unavailable weapons were once made by Blacksmiths; the BC-era weaponsmith specialization weapons.As the heroes conquer the Isle, they will unlock the powerful Lightning Forge, which will allow Blacksmiths to forge mighty raid-worthy items, as well as classic weapons from the past.
While a few people still have their Lionheart Executioner or Stormherald to mog with they're unavailable to the vast majority of players, even ones who had them back in the day. I recall they were mentioned more than a few times during the Mists Beta as candidates for the BMAH. Yet they've remained conspicuously absent till this point. While it's not a sure thing, I'd lay good money that these are what the PTR Notes are hinting at.