What I meant was, if an individual is taxed on their private fuel, they might be better off opting out of employer-provided private fuel and have the fuel card as a 'claim everything but pay back private fuel' facility, as the cost of their private fuel with a 2.0 diesel, might be less than the ~£150 odd a month BIK that you pay as a 40% tax payer. In this case it's worth considering the MPGs of your company car.
I agree with you there, yes, though my original point was about those with fuel cards
