Risotto, or at least the perfected version, is part skill, part luck. The hydration ratio needs to be perfect at all steps in order to get the intended consistency with any sort of regularity. Go to any restaurant that makes it fresh a few times and you'll get different results every time.
The making of Black Garlic is nearly impossible to get right with any sort of regularity, and takes SO MUCH TIME. You're dealing with possible contaminants at so many levels, equipment failure, and just plain luck. Slowly dehydrating while at the same time fermenting something is a fool's errand, and I'd like to meet the insane person who even thought this up.