Nope, not quite. My lifetime average is currently 51 mpg, factoring in both summer and winter fuel mileage. I am currently sitting at about 53 mpg with my mixed driving commute with over 400 miles on the tank. My best tank has been 57.9 mpg, with my absolute worst, bucking a 35 mph sustained head wind, being 37.1 mpg on a road trip to Colorado. I have just under 46k miles on the car now.

All I do is obey the speed limits, and cap my top speed to 65 mph.

I would hazard a guess that if you averaged every fillup on your Jetta since new, we'd probably be within one or two mpg of each other, and this narrow of a gap is where the higher cost of diesel fuel cannot be offset if your numbers are the ones that hedge higher.