Porsche’s CEO, Matthias Mueller, has never seemed convinced by making a variant of the VW BlueSport roadster – whose future is now in doubt – to sit beneath the company’s Boxster.

At the Paris motor show in 2010 Mueller told me there was no point making the BlueSport just for the sake of increasing Porsche’s production volumes; regardless of how much Volkswagen’s advisory board wanted him to do precisely that, from 100,000 to 150,000 cars per year.

Mueller argued that, if the new car stole sales from the more expensive (and more profitable) Boxster, Porsche could find itself in the unenviable position of making more cars but less money. Chase profit, not volumes, he said.

All reasonable enough. After all, how cheap could a sub-Boxster Porsche BlueSport be? Maybe £25,000? More likely £30,000. Close enough, in price and practicality, that even if it reached a new generation of Porsche buyers, it would tempt more still existing ones at the expense of its profitability.

Now, with the BlueSport’s future in doubt after Volkswagen North America decided it doesn’t need the car to stretch its sales volumes to 800,000 units a year, Porsche’s fears will ready another nail for what seems like an inevitable hammering shut of the mahogany lid on the baby-Boxster’s future.

While Porsche can swallow the development cost of the Cajun SUV even if it does eventually nick the odd Cayenne buyer (because the Audi Q5 has already footed the biggest part of the bill), without the VW BlueSport there’s no way Porsche will pay to develop a roadster that endangers its existing sports car. If Porsche wants to reach downwards at all, maybe a modestly equipped four-pot Boxster would be a more palatable solution.

Some of my colleagues argue, not unreasonably, that the 1997 introduction of the Boxster signalled the beginning of the end for TVR. That in the Porsche, former TVR buyers found a destination for their thirty-odd grands without feeling they were doing the development and durability work for the company they’d just paid.

Fifteen years on, for very different reasons, the Boxster is still keeping other roadsters down.