Dagmar
Defender of the Bunnies of Skyrim
How are you measuring damage? The only valid method of measuring damage accurately is through the use of console commands. I'm skeptical as to whether you did this because you didn't post actual numbers which is what's normally done when posting test results using console commands to compare damage. If you're relying on your visual perception of the health bar on the game screen that's completely unreliable....I gauged the damage...
There's also a problem with basing your conclusion on one comparison. If there's a valid variance then it should be confirmed by multiple testing. I generally prefer to run tests 10 times minimum but I often run more, especially if I find something I think is odd.