...possibly.....but then, personally, I wouldn't class someone getting 56mpg average out of a 250 as being your average "real world driver"...!!!
(Frugal - please don't interpret this as "having a go" at you, because I'm most definitely not )
I guess it depends on your driving style. The kind of person who gets less than 50k out a set of brake pads etc isnt going to get those mileages as an average , but driving respectfully of the car and the odd bit of performance i wouldnt imagine 56 is too pie in the sky.
Anticipation and driving to the conditions and not using the brake pedal is the key. Every time that pedal is pushed the mpg disappears.