I think it's definitely overly simple. If it were correct, high-performance cars wouldn't have wide tires. According to Newtonian friction, the contact patch

I think it's definitely overly simple. If it were correct, high-performance cars wouldn't have wide tires. According to Newtonian friction, the contact patch is the same size regardless of the size of the tire. Obviously that's silly; a Lamborghini is not going to get sufficient grip out of economy-car tires, nor would an 18-wheeler. That model completely neglects the complexities of the construction of the tires; they're not like balloons, they're actually semi-rigid.