MPG possible?

[Justintime]

Did a long mostly uninterruped run from Cricklewood to Lewisham today (A5,A406 then A12) about 30 miles, 3 round trips as i'm moving my girlfriend to there and shes got loadsa crap.
My cars a SEAT ibiza FR 1.9TDI, usually run about town gives me 41mpg on the computer thing, today it soared up to 68mpg, did'nt believe it but i'm at 3/4 tank @ 210 miles on the trip computer Cruised mostly 50/60 in 6th all the way up. I usually only see 350-400 a tank muchless 210 to quarter! Is this at all possible or maybe somethings gone screwy?

 

[Justintime]

Ta for the replies. Yes, same with my Ibiza, after half it goes fast, my old Focus was the same, all excited about the great mpg then as soon as its under half it drains away like someone pulled a stop plug (was a good run to get 280 miles to a tank in that one! usually topped off at 260 or so, though it was an auto so that might be why)

 

[Justintime]

The Ibiza's fuel tank is 10 litres smaller than the Leon's. The 350-400 he is getting is driving around town a LCR driven in similair conditions would be lucky to break 250miles.

Heh yep, lots of town traffic and mostly A road rush hour. Also lots of instances of making people eat my soot as well
I could see this getting about 500 miles on a long motor way run though!