I agree. I've read on www.hybridcars.com that there are quite a few flavors of "hybrid. GM, of course, is choosing the CHEAPEST.

"Light" hybrid = Engine stops at traffic lights and stop signs, then resumes when propulsion is needed.
"Mild" hybrid = Idle-stop + IMA helps push the car.
"Full" hybrid = Idle-stop + IMA propels vehicle at slow speed + IMA assists engine at higher speed.

The GM solution would be OK if they weren't planning on still charging +$4,000 per vehicle (like a full hybrid) even though the "light" hybrid system costs less than a grand to implement. The "light" hybrid only captures an additional 2-3 MPG. GM is making the typical Big Corporate mistake of being greedy and cheap at the same time.