All the affected vehicles will get a recall notice but as this is not a safety related issue, it will not be compulsory, owners do not have to get the work done

I would image the majority of owners will not take them in if there is the slightest chance of a performance loss or lower mpg (or your expensive sporty map being overwritten)

Same as in the USA, in California you probably won't be able to drive your vehicle is you do not have the recall done, but the majority of the states in the USA do not even have an emission test for diesels .....so why bother?

I cannot envisage a diesel emission test for the MOT ever being that good in the foreseeable future to weed out the ones that did not have the recall

Just plenty of very cheap VAG diesels around in the next couple of years

Peter