I used to do that with my 62 Impala SuperSport Convertible. Back seat passengers, however didn't enjoy the protection the airflow afforded the front seat occupants. You're right, you couldn't. But it didn't stop Mercedes from producing them for years and years. I believe Miata also has a removeable top, as did the 55-57 T-Bird. Now, if it he could somehow steal the design that Pontiac used on the Fiero hideaway hardtop, and do it like the 58 and 59 Ford Galaxy, that would be the cats meow