good points. i think ken's question relates to the epa mileage estimates on the prius. he wants to know, if what you're saying is correct (and it is), why are the epa city mpg estimates for the prius higher than the highway estimates. i don't have concrete evidence, but i believe that the reason may be that hybrids get a bit of an unfair advantage using the current epa testing methodology. the simulated city driving benefits from the battery being fully charged. when the epa test ends, the battery has not been returned to its fully recharged condition, ergo they kind of got something for nothing. as mentioned on this board, it would be a more fair test if the battery had to be returned to fully charged by driving by the end of the test.