Specialization seems like a horrible idea to me anyway, since you never know which item slots will end up under which professions when it is time to upgrade. Sometimes a class's chest slot comes from leatherworking, but then the next one comes from weaving. Shoes, belts, and hats all bounce around between professions, and even various weapons sometimes come from a class you wouldn't expect. I still remember all of the 2.0 carpenters that were surprised they needed to be alchemists to do the WHM relic weapon.

This is why I still haven't been able to decide on what I want to specialize in, despite knowing which ITEMS I want to specialize in. If you want to lock players into specific categories, lock your items into specific categories first.