Stop start definitely is used during the tests. ... a larger proprotion of the test is spent stopped than in normal driving.
Guess we're going to have to agree to differ here !
My reading of both the link I posted to the VCA site, and the more detailed description of the ECE-15 test cycle (here:
https://en.wikipedia.org/wiki/New_European_Driving_Cycle) is that the engine should remain idling, not be stopped; one of the many criticisms of this testing is that the official cycle is so old (1970) that no-one had thought of stop-start at the time so the test doesn't permit it. Even if it is permitted, the test specifies that the engine is started from cold so the stop-start wouldn't kick in anyway during the short urban test cycle. Happy to be corrected if anyone can provide a reference proving otherwise.
Also, if you add up the numbers in the wiki article you find that a car under test would be stopped for 240 sec during the urban cycle, but moving for 540 sec; the extra-urban cycle adds a further 400 secs moving.
... if you are paying extra for a car fitted with it (and you will be) what benefit can you expect as a 'pay-back' if not a reduction in your fuel bill.
My point was that environmentalists jump up and down to get these technologies and don't mind car prices rising because of new technology with limited gains - they probably see it as a big plus if people can't afford a car and have to ride a bicycle.
I wouldn't consider myself a rabid environmentalist, but if I can contribute in a small way that's great, and if it costs me slightly more then so be it. After all, I bought a Jazz, didn't I ?