I don't believe the relational model is as rigid as you described. The fact is that there are many different ways to model the same business concept in the real world. I've never seen two designers came up with the same model for a business application.

The real difference? By the end, the one performs best wins. Because the best design must be measured by both functionalities and performance in the real world. Focusing on one but neglecting the other would only lead to failure of the business in the end.

Nice try though.