I just felt like taking the thread further off-topic 🙂
If the Fiat and the Porche leave Oxford at the same time, the Porche will get there before the Fiat unless it gets stuck in traffic (or behind the Fiat). It is a faster car.
Only if there were a traffic jam would the Porche take as long as the Fiat. But if a Citroen 2CV then joined the race, the Citroen 2CV would win. Because it has phenomonal off-road capability, it can cut across ploughed fields carrying a basket of eggs on the back seat without any getting broken, so it could avoid the traffic jams by cutting across fields. My comment about 5 litres was incorrect. The 2CV would also need 6 litres to cover 56 miles.
On a more serious note, your analogy is imperfect. A better analogy for weather comp would be that a car run at 60mph and using slow acceleration will take a little longer to get to London than a similar car driven hard but stopped for frequent breaks but will use less fuel. Because, after all, the point about weather comp is that it improves the efficiency of the same boiler by "driving" it in a different way.
Silly though this discussion may sound, we may as well have the discussion here as we need to rehearse for when we explain to customers.
