Hmmm… interesting.
To understand the two, I usually say that ITCSS is an architecture, and inuitcss is the embodiment of it. They share the exact same philosophies.
ITCSS: flat file structure vs. Inuit: directory-based
ITCSS doesn’t actually prescribe a directory structure; you can use whatever you wish. For a while I had a demo which was flat, but most people do (and can) implement it in directories. The primary idea of ITCSS is that it’s flexible enough that the implementor gets to make a lot of decisions.
ITCSS: DRY vs. Inuit: Node install requiring potential overrides (a la Bootstrap)
ITCSS aims for reduced redundancy, but can never completely eliminate it. That’s why inuitcss does often require a few overrides, they are definitely minimal. inuitcss also has a lot of preconfiguration which would hopefully reduce the amount of unused CSS in there.
So yeah, the intention is that they’re not really different in approach at all: inuitcss is just what you get when you put ITCSS’ theory into practice :)