Today, for the first time I checked Trip 2 (I normally monitor Trip 1 which is the single trip memory, Trip 2 is since it was last reset, in my case since refuelling). The "Fibometer" tells me I have managed 29 mpg so far this tank. Obh, obh.
The only saving grace is that all the trips have been short (2 or 3 miles) and in the city.