Don't want to stir it up more here , but I can remember reading that Xenons have washers because the light they produce deteriates more than halogen light when they get dirty. I think that , strictly, they are not legal without the means to clean them and keep the required lighting. With the MoT , its probably the case that its just not enforced properly. Is it a case of the tester thinking "if its not on the car, it doesn't need testing" ?
Chris.