Another way of fixing this problem would be to make the purple crafted items bind on equip and allow players to sell them on the ah and hand them out to their guildys. also making it so that the items are unusable if you switch to a different crafting is ridiculous, by allowing people to change crafting it allows them to find an additional time sink leveling a new crafting set and having to learn all of the new schematics removing that ability because your already crafted items will no longer work is disappointing.
A friend of mine pointed this thread out to me and said but wow does this with their crafting, my only response is that with everything this game currently has going for it why copy something like wow when there is a better way of doing it. This fix will only limit the crafting system and remove another time sink and money sink that this game has, if these items only work for biochem users then biochem will still be a requirement because you cant use them at all unless your bioche. This does not fix the problem, in fact it doesnt do anything to fix the problem at all.