The tricks up my sleeve... Methods I may implement for better FE.

[Wyldesoul]

There's also the matter that I highly doubt that in EPA tests, they make sure not to use the turbo.

When you engage the turbo, you jam more air into the engine, and therefore more gas to keep the stoichiometric A/F ratio.

Of course if you get into the turbo, you'll use more fuel.
I've found that at least with the Ford 2.3, the Turbo gets around the same FE as the N/A, highway at least. City, the turbos usually get less than the N/A, but that's because you do a lot more accelerating, and therefore use the turbo a fair bit more.
Well, that is with the average cars, and average drivers.

Quite obviously in tests they'll use the turbo, but if you don't use the turbo, the cars usually end up having the same FE.

I'm not trying to decry you guys, but I'm just going on the experience that I've had with owning both N/A and turbo ford 2.3 cars (Mustang 2.3, and Thunderbird 2.3 turbo), and what I've gleaned from frequenting the forums for both cars.

Turbo charging seems the best way to add lots of HP without sacrificing FE. Get rid of all back pressure in the exhaust system, use the turbo for the back pressure, and know that you have power if you ever truly need it.
Just keep the delicate foot that has been trained to maximize FE, and you wont ever build up enough exhaust velocity to engage the turbo. There will be a restriction to the intake, but at partial throttle, that won't make much of a difference.

My opinion based on experience and my knowledge. There is a rather good chance that I'm wrong, and that when you start getting into the really high FE realm, that a turbo, even when not engaged will sap the FE, but at the realm I'm at the N/A and turbo have very little difference in FE, and that seems to be the average across the board for most owners in the forums I usually frequent.