Holy cow! You opened my eyes! That is unforgivable stupidity from my side. Of cause Granary increase efficiency by 100% (doubles)! And all whip hammers are still subject to other multipliers (like Forge +25%, etc). Last games I haven't considered 100% Food -> Hammer boost from granary trying to keep high population intact. I always need to whip at least X+2 => X. Constantly. X+2 should be Happiness limit.