well being a DIY quilt newbe and all, I knew that 900 was "better" than 850 is "better" than 650 and so on, but didn't know or look up the units. But if I'd done your math I still would have been confused, because 4.32 oz is still between 1 bag and 2!
but I'm on it now. All I need is 1.1 oz camo and I'm in business. Oh wait, there's down to get. And a vacuum cleaner or something if I remember right. And that time thing...
thanks for the explanation-by-numbers