The Second Expert Crafting Test
I just found out that to get the quest for your second expert skill you have to complete the first quest and then raise your skill in that profession to 449. Only then will the second quest become available.
If you accept the expert quest for the first skill, (Alchemy, for example) then you have to complete it. You cannot abandon it and then pick up the other quest.
So my Assassin has the 399 Alchemy and accepted the quest for expert in that skill, but did not complete it. I then raised her weaponsmithing skill to 399 and was able to do part one of the quest, but the main part never became available. After much googling (and forum reading) it became clear that I had to finish up that first quest, first.
I did try abandoning the alchemy quest, but the weaponsmithing quest did not become available. Apparently this is working as intended. NC says that it’s meant to be tough.
It seems to me that it would be easy for NC to insert a bit of dialog here. Just have the Master crafter tell you that you have to complete the other quest first, that you can’t abandon it, and that you need to raise that skill before you can accept the new expert quest.
Ok, back to the grind. 
