As I understand this kind of system, it doesn't rely on a load of extra batteries, correct? GM needs to advertise the H E Double-L out of this. Make it an issue for the greenies, that their precious lead-acid batteries are going to be filling landfills as a result of using 'regular' hybrids.
"By developing a Hybrid system that does not use lead acid batteries as a source of power, we greatly lessen the impact on the environment, reduce costs, reduce maintenance, and increase safety for emergency personnel in the case of an accident."