And the remaining question - what happened to the cake? Barker says they looked at donating it to charity, but by the time the cake had been in the studio and under the lights during construction it was not thought fit for human consumption. It ended up in a compost heap - though the chocolate speedometer and marzipan wing mirrors were, reportedly, kept for posterity.
This is an enormous amount of trouble to go to for an advert - some estimates say that it cost £500,000 to make; one newspaper pointed out the comparative value of a Skoda (the advert costs 62 times as much).
BBC NEWS | Magazine | No piece of cake