You're the one that came in and told him about the "factor in your math". Like you said, it's his comparison, not yours. If you want to do your own comparison,

You're the one that came in and told him about the "factor in your math". Like you said, it's his comparison, not yours. If you want to do your own comparison, feel free. But don't come in and tell him he's not allowed to do his comparison. I for one like is comparison.