Better mileage when not in eco mode

mikefocke, that's how I drive too except I just leave it in normal mode as my personal preference. Letting the car do the work is the right way. Forcing EV mode is counterproductive as stated in the owner's manual.

As a thought experiment, say somebody deposited you, one gallon of gas, and your Prius on the Bonneville salt flats with ten other similarly equipped Priuses and owners. And say there was a $1MM prize for the owner who traveled the furthest on that gallon of gas. What would your strategy be?

First I'd get rid of all the ballast I could because A = F / M. Then I'd accelerate gently up to 35-40 mph then hold that speed with cruise until I ran out of gas. Then I'd try to maintain 20-25 mph until the battery depleted. At no time would I want to regenerate if I'm going for distance, and I would want the engine running continuously until it ran out of fuel. At no time would I operate the HVAC, lights, or even the radio or a cell phone charger.

To the extent you can drive this way in the real world, that's the way to maximize fuel economy. To the extent you can't or don't want to, let the car do the work. Simple as that.