I am getting 43-44mpg from my 2.0 180 automatic diesel S-Max, the 1.5 petrol in the same car is dire at under 30mpg.
My previous 1.6 120 auto diesel Grand Picasso averaged 47-48mpg on the same run, driven the same speeds. In the S-Max the whole thing is effortless, the Picasso not so much – a tad breathless if you needed a swift overtake.
I do over the cap every year, and I drive as I always have, albeit slightly slower now my commute is on average speed camera monitored dual carriageway.
In life, it's not who you know that's important, it's how your wife found out.