How to convince partner that logo shoeldn't be on top of every window

I am working on an app with a team of a few people, and one of those people keeps saying that the logo of the app should be in the middle of the navigation bar in every window. I have been telling him that this doesn't conform to the HIG and it doesn't look good at all, but he doesn't want to believe me. How do I convince him that this really isn't a good idea and we shouldn't do this?