Not because he needs it or that it would change much overall, but I don't think Nasus should be punished to purchasing an item which forces him to lose Q stacks. I'll always be in favor of itemization choices being positive for the player, and not negative.
That being said, I don't think this change would really effect much, as the IBG damage doesn't one shot minions. You still have to farm intelligently as any other AoE clearing champion already has to do. --- "You're not quite courageous enough to take that risk. You need to be a Badass first." -Persona 3