[jax55]

The cloth top is covering a wood frame that does not collapse into a convertible and the Landau irons are for looks not functionality.
The 31 Sport Coupe I have was turned into a convertible by removing all the top parts and cutting the window frames off the doors. I am in the process of putting it back to a real Sport Coupe.

I think if someone wanted a sporty look but not a convertible, the sport coupe was the way to go. A coupe was more of an "everyday" car.