I have read Anna Barrington's article of her views, and I will give you mine for what they are worth. Regarding so called de-tuning it's down to a thing called inertial mass. Compression ignition (diesel) engines fire due to a compression ratio significantly higher than petrol engines. So all engine components have to be stronger to withstand it. Stronger means bigger/heavier. That coupled with the higher compression ratio means a bigger bang. The bigger bang per cycle means a less smooth revs it's countered with a greater size flywheel to smooth out the individual firing pulses.So, you have a bigger bang, stronger components and heavier flywheels and were back to the mass. Higher revving would literally fly the engine apart. So all diesel engines are governed and have safety margins for good engine life. So up the fuel = lumpier engine and reduced engine life or go the whole hog and you can push a diesel to destruction, old diesels had to be governed the governing now is done by the ecu which you are fooling. The amount of air, and fuel injected into the engine is not some random amount as suggested by the article but a highly regulated amount mainly regulated by the air flow meter to give the most power and economy for the amount of fuel used. So if you fool the injectors to put in more diesels, yes you get a bigger bang but you are also running rich [more soot for the dcp to remove] less economical and running lumpy because the flywheel is not designed for it. And as for getting more economy on acceleration because you don't have to put you're foot down as hard the car moves quicker with very little throttle. That's right you only have to touch the throttle slightly because you're little box is pushing the fuel in by the bucket full So diesel engines will run to destruction its not de-tuning its preserving engine life and economy. Effortless acceleration, no banging extra juice through to make it look that way. The captive is getting bad press for not very good fuel economy so why not fit a magic box to them all and save the new purpose built captive engine they must have spent millions to develop, but no the new model is throwing out that engine and fitting it with the Kia 2.2 more economical engine. Come on lads can you not see the elephant in the room!!! That's me done on this topic, if you all still want to by a box don't forget my offer of being able to live for ever for a £5.00.