Lil, or one of you other knowledgable guys, why would he need an 80-85 spine when he's drawing 61-62#?

Im not trying to be a wise guy, I have a Crusader ordered as well. I thought that your spine would be close to your poundage, ie: A 55# bow would use 55-60 spine, or close to it. Is there something I am not seeing here?