Phew, another personal best C30 instrument record!
This beats the last posting by 35 miles. Remember, this is artificially high (and pretty much unachievable) because it is the result of driving carefully and them immediately filling up. It is clear you have to be driving efficiently for some time anyway but to get these figures you need to stop for petrol at the end of a long journey home. Any last minute starting and stopping impacts the estimate. If I stopped at home first and then filled up on the way out to work the next morning I probably will not see these figures.
Unfortunately, as you can see, I only managed 683 miles on this tank (‘only’ – he says!?) with an indicated 100 miles to empty before stopping for this load of fuel.