I'm definitely in favour of much more punitive taxation for the higher
classes. However, I hope they don't get too arsey with 7 seat Group E
vehicles.

Why?

Fuel savings comes from all the little cars NOT doing the school run, NOT
doing a supermarket run EVERY DAY and not doing 100 mile commutes every
day.

By taxing at a rate that is greater than proportionate to use, you are more
likely to affect behaviour.

I just think that the number of seats in a vehicle should be taken into
account to some extent, as the extra seats will take other vehicles off the
road, reducing effective emissions. Obviously, this can't be overdone, or
people will simply buy cars with more seats that they don't need. By
dropping a band by having 7 (or possibly 6) seats or more, or rising a band
by having 2 seats or less, the market will actually be less distorted and
the tax more in line with the likely CO2 emissions per person/km.

Christian.