Fuel economy is a fancy thing these days. Catalytic converter must not overheat or it might melt/die, so it simply dumps too much fuel under wide open throttle to cool it down.
My car in stock form doesn't even use power enrichment, it relies on "temperature protection" to add additional fuel for on-boost power, and this temperature protection doesn't even know the actual temperature of the catalytic converter, but uses some fancy formula to estimate it. There's really no point to dump that much fuel to cool the cat when all i did was a 2nd and 3rd gear pull and then continue to drive normally.
This is a very broadly used engine, and every car model is different, and every cooling system for a different model car is different (and the airflow around the exhaust components) - BUT the base tune is the same across all of them.
As for the AFR number, adding more fuel displaces oxygen therefore you actually lose power. Very small, but measurable. Removing fuel actually increases power AND reduces fuel consumption at the cost of some components maybe running hotter. You can get more out of a generic customer car like this, than a straight up sports car that's tuned from the factory to the limits.
Driving on the highway under no-load and fixed speed can be improved by running even leaner and advancing spark timing, it results in lower fuel consumption and same power output at the expense of different exhaust gas composition (google honda lean-burn system).
This is only a rough outline, but there's so many places where you can save on fuel in the map files.
There's also the point of CO2 and NOx emissions, more fuel -> more volume of gasses -> SAME ACTUAL amount of NOx in the exhaust stream -> "less percent" of bad gasses per mass of exhaust.
And that's how you get numbers that look nice on paper to show to your local government/european union and make the impression that you're eco friendly.
My car also isn't listed on their main page, but it's the E78 ECU and same engine and it works just fine.
You can post any questions regarding your tune on the forums, and we'll try to help when we have time.