Agree with the driving styles comments... I learned many years ago to accelerate quickly but not agressively, don't tailgate and know where the stops are going to be. Not only does it help with the gas mileage but it does wonders on saving on brakes. A few vehicles back, I was able to go 75K on my explorer before the brakes needed replacing...
With the TDI, I lucked out and hit a sweet-spot with my commute. I'm averaging 39mph (speed) on my commute of 25 miles (one-way) that will vary between 25mph and 45/55mph depending on the exact route I take that day. the tdi loves the rolling hills. Some days I have exactly 2 stops (signs) the entire way.
With the lack of summer here in NewEngland, not needing to run the AC very often certainly has help keep my mpg up. It will be interesting to see what my averages do in real summer weather in the future.
If you've been a TDI follower you will know that there was quite a controversy when the inital 2009 TDI EPA numbers were finally made public. This was around 15 months (or so) ago... I've got one of the first 09 units and have been running it for 50weeks now and am really happy I waited for it and bought into the believe that they had to be better....
mathowie, you have to realize something....it's not that Honda hasn't progressed in the last twenty years, they were miles ahead of everyone else in the late 80s where fuel economy is concerned. The rest of the industry has caught up, that's all.
"You don't need to be an eco-nazi right-lane vigilante to get better mileage out of *any* vehicle - just be engaged and drive SMART."
No. You actually do really need to drive slower, and therefore in the right lane, in order to get the kind of numbers you're getting. I see your best is about 56 mpg/tank. You're either driving slower (ie, <= 65 mph) or you're using imperial units. There's no way around the laws of physics.
My TDI averages 48mpg while on the highway at 70mph. On long trips I have found I can still drive 80mph and get the same mileage on my 2001 Jetta TDI. I could drive slower and get crazy high mileage, but I 50mpg sounds good enough to me.