I understand your math, Eman, but I think the word "theory" is the salient point. Theory is good, experience is better. In my experience, 20-25C rated packs tend to get hot, even in my "little" 35A EZrun system. Now I suppose it's possible that Gens Ace over-rates their batteries, but I have found that 20C or even 30C 2S LiPos get well over 110F, where 40C or 50C packs stay below 95F. Based on that, I would suggest the OP get higher C-rated packs for his 100A ESC.
FOXY, what do you say?