A wizard (that must have high score in Intelligence for casting high spell levels) with only 3 ranks in one ability that halves the price of all magic item? An ability that give him a super-rewarding job and very useful in large spread of gaming actions? Seriously? ^^
In my opinion adventurers have very much rest time from adventure to adventure, time for crafting is no trouble at all.
Wizards can easily spend rest time to craft for himself and for others gaining monstrous amount of gold pieces and powerful magic items without a single chance of fail in the process.
Making spoons, goblets, common swords are considerable routine tasks, how is possible that making Brilliant Energy Vorpal Longsword +1 can be considerable routine task?
It's a broken rule, very unbalancing for me. ^^