As said in the OP, for some reason I cannot fathom, SE has decided not to make the i70 WVR/LTW/CRP Artisan's items from Talan desynthable. They gave a "reason" ("the newest gear is never desynthable"), except it's trivial to prove that is completely untrue. The i100 sets from the 2.5 dungeons were desynthable at release, for instance. So, it's just a really weird decision that makes GSM, BSM, and ARM the only desynth classes that can (realistically) acquire MCDs. Hopefully, they'll be more consistent and sensible in 3.x with whatever the MCD equivalent is there.