Selling cars is not unlike selling homes. If you put a buyer in a product that is actually beyond the means of being paid off then another repossession and foreclosure era will be revisited.
I think realistically, that the U.S. Market will not return to 16+ million units a year in the near future. And if we have learned anything from the financial meltdown, the sub prime loans should all but dry up. This obviously should impact the sales that put buyers in an upside down financial position after they purchase a vehicle.