The Ocean Drive concept was rated only an outside chance for showrooms, until Rolls-Royce confirmed production plans for the Phantom Drophead Coupe at the show this week. It's a move that's sure to spark interest among mega-rich fans of open-air motoring.
The British company is already talking about waiting lists and long delays in Australia, despite a price beyond $1 million, and it will probably be a similar story in many other country, with multi-millionaires racing to get their hands on the Phantom convertible. The Rolls-Royce announcement was predictable, even if it did not bring the expected return of the Corniche name that has been previously used for open-air Rollers.
But that did not stop an instant reply at the Mercedes-Benz stand.
"It looks as if Rolls-Royce is going to be responsible for Mercedes buyers getting their hands on our new convertible," a Mercedes-Benz US source says. "It is almost certain to get the go-ahead now."
The big Benz is being displayed only as a concept in Detroit, but is clearly more than just a dream machine.
It shows Mercedes' thinking on everything from body styling to the pillarless side panels needed to make the car a workable production model. They anchor the rear doors and ensure the sort of access to the back seat every other convertible and coupe owners can only dream about.
Based on earlier show-to-road programs, it will probably take about three years for Mercedes to transform the concept to a production model. It is based on the S-Class but has different styling, even from the super-expensive CL coupe about to go on sale in Australia.
It is much more bluff, with giant wheels and a two-tone paint job that are unlikely to make it to production.
But the upright grille could easily make it through the system in Germany, along with the electric folding soft-top roof and Benz's "airscarf" heating system that blows warm air over the occupants' necks.