But that shapely concept car, which Ueda’s studio in San Diego, California, helped to create for the 2013 Detroit auto show last month, offers only veiled hints at the future of design for Nissan, whereas right next to the brand’s stand at the Toronto auto show is the 2014 Infiniti Q50 sedan from the automaker’s luxury division. This, he said, is a car that bears clues to the Q60 coupe – not expected to be shown until 2015.

Specifically, Ueda identified a tapering strip of brushed aluminium, the so-called “crescent cut” behind the rear door, a design element that will be carried over to the coupe. “We think this is one of the signatures of the Infiniti brand,” he said.

Automakers have long used door real estate on a car to create a brand signature, to varying degrees of success. BMW may be the most consistent of all mainstream brands, having pioneered the Hoffmeister kink – named for the company’s mid-century design chief – distinguished by a low forward bend in the chrome directly behind the rear-passenger window glass.

Adapting Infiniti’s crescent cut for the coming Q60 model presents its challenges, Ueda said. “How we harmonise it with the surrounding body, we have to take a different approach than we did with Q50,” he said. “It has to be a more strong accent.”

Whereas BMW’s kink has proven remarkably adaptable, looking at home on a low-slung 6 Series or a more upright 3 Series, Infiniti’s crescent cut has yet to be asked to downsize. Is “strong accent” synonymous with “squashed accent”?

“No,” Ueda said.