On a related note I recently saw advertised a device that disables Displacement On Demand because, you know, if you have eight cylinders then By Gawd they ALL better be firing at ALL TIMES.
I didn't realize cutting some cylinders when the computer decided they weren't needed and then seamlessly (?) restoring their operation when they were was an issue.
But then, I didn't and still don't realize the necessity and awesomeness of remotely starting my engine and letting it run while the vehicle is stationary and unoccupied either.