Illumunaire

Just like with steel protection bubbles and advanced shaping of time dilation fields, there is a way to direct or extract only what you want out of allomancy and feruchemy. Wax and Wayne are able to use allomancy in ways that practically no one else can, just through experience. For feruchemy, it's probably much harder to become experienced like with allomancy, just because the attributes take a long time to store and are more valuable by comparison. There's probably some way you can actually store and tap feruchemical gold at the same time, suppressing health in certain parts of your body, and advancing it where it is needed more. If healing factor always heals the parts that need health most, then it's possible healing will also suppress the parts that need health least. Therefore, with careful direction, you could speed up recovery of brutal injuries even with no net gain. I may be wrong though. Like you couldn't tap more than one feruchemical device at the same time or store and tap at the same time or something. I feel like this is the direction that B.S. is going though. That the information we're given isn't whole, and that there's plenty you can do with the powers that no one has discovered yet. It was like that for allomantic bendalloy and steel, who's to say it couldn't be the same for feruchemy as well?