But the pendulum has swung. The 2005 Honda Accord hybrid gets about the same miles per gallon as the basic four-cylinder model, according to a review by Consumer Reports, a car-buyer's guide, and it saves only about two miles a gallon compared with the V-6 model on which it is based. Thanks to the hybrid technology, though, it accelerates better.

Hybrid technology, it seems, is being used in much the same way as earlier under-the-hood innovations that increased gasoline efficiency: to satisfy the American appetite for acceleration and bulk.