There is a lot of incorrect information in this thread-
"The gas engine is run constantly at its most efficient RPM setting, and therefore cranking out the most energy per amount of gas ...."
This is utter rubbish. The gas engine turns on and off as necessary. The Electric motor is the primary drive unit. Around town, in the Synergy Drive system of the new Prius, you can not have the gas engine turn on at all.
Regenerative Braking means taking the energy used to stop a car, and instead of turning into friction/heat via brake pads, you turn it into energy that re-charges the main batteries.
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The main point you all miss.
ALL cars have combustion engines now. There is no infrastructure for hydrogen, fuel cells yet. So, you throw in an electric motor that compliments the gas engine, you can reduce the use and size of the gas engine, and when it is needed, let it charge the electric system.
It's a closed cycle. Smaller gas engines can be more efficient, and the electric motor puts out 100% torque at, get this, 0 RPM, yeah, instant GO.
The truck statement is not applicable here, can a motorcycle tow a trailer either, wtf is your point? We shouldn't try to save fuel and lower pollution, or that your big truck makes up for your non existent knowledge of regarding energy efficency and sustainable means.
BTW: 2004 Motor Trend Car of the Year - Toyota Prius (a hybrid)
George