BGWiki said:
You can take all crafts to level 70 skill this way, but currently you only have 40 points that you can use for crafts in excess of level 70. These points do not have to be spent on one craft, but exceeding your 40 point limit will lower your highest skill level by an equivalent amount. You can revoke your skills over 70 and ranks over Artisan for all over crafts by speaking to Guild Master of the craft that you wish to remain over 70. Example: You could have one 110 craft, 2 level 90 crafts, 4 level 80 crafts, or many other point distributions. If you have a level 110 craft and you unlock and skill up another craft 0.1, your 110 craft will drop to 109.9 because you have exceeded your maximum limit.
This is definitely how I remember it working. So, it's broken?