Yeh I think there may be a correlation between ILI-Ni and 4 wing but also Te subtype and 6 wing.

It makes sense in that Ni is more introspectively inclined and Te is more scientifically inclined toward dissection of fact; 4s are supposedly interested in things like humanities, philosophy, art etc while it says that 6s are more apt to persue things like law, exact sciences etc.
Different emphasis could mean ILI 4w5 and ILI 6w5, but I can't see a 6w7 or 4w3 existing anywhere.

I really need to make an ennea database...