GM didn't want to spend the time, or spend the R&D money, to make this crap-tastic system happen,
they were forced to come up with something by our tyrannical EPA and the ever changing CAFE standards the EPA imposes.
No matter what anyone does to 'improve' MpGs, fact remains, our SUVs are
80" wide, over 6' tall, 5000lb / 6000lb bricks.
Newton's laws demand a certain amount of energy be expended to move 'em.
Cylinder valve deactivation and 10speed transmissions are pretty much the proof that
we've crossed the point of diminishing returns in terms of squeezing more MpG from a drop of fuel.
One way or another, end users will pay for every single 'technology', whether it works or not.