Novus weapon upgrade system findings

[Shea]

have you tried to infuse a IV with having 4 alexanerites?
I am wondering if you look at it like normal materia melds on crafted gears IVs will require 4 alexanderites?

I've pondered that as well, thinking maybe it's just worded wrong. The wording is along the lines "Materia of a different grade is required to enhance this attribute" yet I have all grades 1-4.