I don't get this "NM is there so that you don't get scrubs in Savage" talk.
O1S and O2S are barely harder than O4N, and then there's a massive difficulty spike from O2 to O3 so even if you manage to clear THOSE fights that won't mean you're ready for the rest of Savage.
Plus you have fights like Shinryu EX which is also harder than O1S and O2S yet it requires neither the completion of those fights OR the completion of Deltascape normal mode...

I persoally agree with Commander Justitia, O3S would've been a much cooler experience if I hadn't already gone through a dumbed down version of the fight which spoiled me on half of the mechanics, which is why I actually really enjoy O4S (once you get past Exfaust anyway).