My sympathy for car makers in the field of emissions and economy testing is pretty limited, having evaporated with the revelations of Dieselgate and subsequent understanding of just how lax the regulations were that they were playing to in Europe.

In that regard, the rollout of the WLTP (Worldwide Harmonized Light Vehicles Test Procedure) and RDE (Real Driving Emissions) regimes should be welcomed with open arms, replacing, as they do, the laissez-faire NEDC (New European Driving Cycle) tests in a staged format over a period that began last autumn and which runs until 2021.

During that time Europe will go from having regulations that were so lax that they allow the Volkswagen Group to state to this day - with what remains a legally watertight position - that its cheats didn’t actually break any rules, to ones that are widely regarded, even by critics, to be the toughest in the world.

So three cheers for the legislators, belated though their action may be, and inept may their predecessors have been.

Except in one crucial regard: it is, perhaps inevitably, the car buyers who are going to be paying the price for the changes, both in terms of the added costs being passed on to the car buyer and, for the short-term at least, there being less variants and options to choose from.

How so? Chiefly, because the new test processes are so unbelievably complex. Where a single lab test was once enough, a new, longer, more complex lab test is now required, plus an on-the-road one. Experts at Mercedes-Benz, who have got on the front foot in trying to educate people about the new systems, estimate the test processes to take at least twice as long as the old ones. They also highlight that during the transition period they will still be doing the old and new tests, to help with calibrations.

What’s more, while their workload has doubled, the amount of backend organisation, paperwork and administration has soared exponentially. The same experts struggle to put exact figures on it, but will ruefully admit that procedures that once took weeks now take as many months. So that’s more cost that will inevitably be passed on to the customer.

So tough are the tests now, that even the addition of a roof rail on the spec list now threatens to require a full raft of separate emission and economy tests. Again, there are laudable reasons for this: if you buy a car with some options on, it is good to get a guide of the impact they will have.

But just imagine the complexity of either having to calculate for every option, or to actually retest cars with the options on (which way they do it depends on a complex formula). The amount of work the car makers are having to do - as a result of the regulations being defined late, not because they left it late - is extraordinary. Anecdotally, there are reports there isn’t a certified testing dyno in Europe that isn’t booked up for years in advance now.

The net result? Certainly as the cut-off date for WLTP compliancy thunders down the road for September 2018, it is that car makers are desperately rationalising the variants and options they offer, to minimise the workload they face. The same Mercedes experts weren’t about to give details, but they did hint at the issue. “There are a lot of jobs that have been put down the priority list,” said one. “We think the new rules are a good thing, and we will hit the deadlines - but the workload is immense.”

And to what end? In the broadest of terms, we can expect the official economy figures to drop around 22% on paper (although, of course, it is by no means that linear). It is great that the car-buying public will be getting more accurate indications of what their cars will actually do in the open, and absolutely right that the car companies are both being held to account and being beaten with a big stick to improve.

Consider, too, how these new figures will be used in time. Most likely, from 2020 they will be applied to calculate VED and company car tax bands. The Treasury must be rubbing its hands in glee at every car suddenly recording CO2 figures that are more than 20% up in average - and, again, we’ll be the ones paying.

But it’s also true that for all the figures will change on paper, they will remain the same in the real world, by which I mean that an engine that is certified differently is still the same engine. It’s also true that the official figures will still vary differently from what most drivers actually see, the variables of driving style, weather, traffic and road conditions still being at play. It doesn’t help, either, that the on-road PEMS (Portable Emissions System) test kit used for the RDE tests can record results that vary by as much as 50%, such are its limitations.

The car-buying public deserve to have figures that are robust and that they can trust, and that legislators can in turn use to enforce scientifically based standards, but for the short-term at least it pains me that the means to that end comes at the price of rising prices and reducing options.

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