I'm not opposed to overdrive gears, either, though I'd rather there be just one. They're great for cruising, and let's be real here, barring something like the N'Ring, what racetrack would allow you to run up to 7th/8th gear anyway? On the vast majority of tracks around the world, a Corvette would likely never go beyond 3rd gear. The only time it would matter is a V-max run, and who really does that in stock cars anyway? Even in something like the Texas Mile, the highest gear you'd reach is 5th, so the overdrives wouldn't matter there either.
What I'm opposed to piling on weight where it doesn't need to be. Safety regulations and the demand for interiors with every possible creature comfort are already turning cars into porkers, and all this fuel-saving stuff is just making it worse.