One counter-argument to that is that many (I won't say most since I don't have sources) PHEVs don't get plugged in too often and are only bought for the tax adv

One counter-argument to that is that many (I won't say most since I don't have sources) PHEVs don't get plugged in too often and are only bought for the tax advantages. An issue in some countries which give tax advantages to PHEV buyers, especially for company cars, where the driver doesn't have to pay for petrol.