iheartthed, I do not think the two issues are mutually exclusive. It may be that the region needs to constrain growth as a whole, but Detroit as a city also needs to face certain realities, including the following:

1. People are fleeing the city for elsewhere in the region and outside the region.
2. The city was laid out for a population of nearly 2 million, whereas the population now is more like 800,000.
3. The city is nearly broke, and with people leaving and property values declining, the tax base continues to shrink. Without taking action, the cost of providing services will not correspondingly decrease.
4. It is unlikely in the near term that any kind of revenue sharing system with suburbs will be approved.

Given these realities, I think it is completely fair for the city to consider what it needs to do to "smartly shrink." Or perhaps it would be better to use Frank Popper's term, "Smart Decline." The city needs to take action to improve its structural finances, and also so that it can more effectively provide services to its residents.

That said, regional sprawl is something that can also be addressed, and I do not think one must pick one or the other.