I can't speak for the Prius, but the HCH numbers are pretty close to what I see when driving normally. By 'normally' I just mean driving 70 on the freeway with cruise control, and accelerating at or below 2500 RPM in the city, and coasting when possible (no other hypermilimg techniques).

So I wonder if this means that the nature of the EPA test somhow favors the Prius' strengths?