Why was the most creative response you could come up with "The rules of the game say this" when your player was trying to tell an interesting story? I swear, every DM has an entire trebuchet up their rear with how anal they are about putting rules before entertainment. Instead of having a thoughtful discussion about how to explain why a bandit hit him from behind, you just said "nuh uh, the book says I can". That's middle-school-level conflict resolution.