By 2009 Porsche had well established the idea of its badge appearing on the prow of a five-door model.

Seven years of the Cayenne had left an indelible mark on the brand; if the conditions were right, it was capable of anything, no matter what tradition had previously dictated.

Yet the appearance of a saloon was almost as controversial. Porsche had pondered the idea for decades, even creating an ill-fated 989 prototype in the late 1980s, but the idea was greeted as a misshapen spanner in the internal machinery of the world’s most renowned sports car maker.

The look didn’t help. The Panamera’s Porsche design cues were stretched to the limit of credibility and beyond.

There were other flaws, too. But it was engineered like the Tirpitz and in the right spec could leap continents in mighty bounds. Its audience was dramatically smaller than that of the Cayenne, but it was chairman of the board-shaped and respectable.

Helpfully, it suited China’s burgeoning back-seat luxury market to perfection. The model was updated in 2013, but not to the point where it destroyed the opposition in the way the contemporary 911 managed.

This latest version, though, can claim a much more credible level of newness. It is bigger, reshaped, remodelled inside, overhauled in the chassis and endowed with Porsche’s latest engines and gearboxes.

After seven years, the Panamera no longer has to prove itself against the stigma of contentiousness; the mission now is to make Porsche’s idea of a four-seat GT seem unequivocally more appealing than BMW, Audi, Maserati, Mercedes-Benz and Jaguar have managed in the meantime.

The manufacturer has promised to redefine the performance benchmark in the luxury class. We chose the 4S Diesel with which to examine that claim.

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