Nah....pure skill as a driver

Serious, don't know MH. I know the computer is about 0.5-1.5mpg optimistic from my checks, but that still equates to about 51.5 ish ? I think maybe part of my "success", is that my 10 miles on the Motorway each night (M62), whilst pretty much always moving steadily with few real hold ups, only travels between 55-65mph most nights due to the sheer volume of traffic, I guess that's the sweet spot for fuel efficiency.
As an aside, I had a stark reminder this morning of how much the colder weather affects it. All this week leaving for work (about 6.30am ish) it's been below freezing, so with the heaters on full (yes I'm a softie and like my comfort), which obviously means the PET heater is switched on as well, heated seats and heated rear window, I've only been getting about 41-42mpg going to work (which is though a major city - don't use the motorway in the morning). However today, exact same journey, but the ambient was now 10°C, I got 48.7 mpg !