I just accepted a master clothier's writ, ported to a guild hall that has all of the set-crafting tables, noticed that there's no pointer above any of the tables, took a closer look at the details of the master writ, and realized that it isn't for set gear, just an Epic Malacath Rubedo Leather Belt with Divines trait. Is it a bugged master writ, or did they add master writs for non-set gear?
I've fought mudcrabs more fearsome than me!