Wag the Dog or Small Cell Backhaul?

We have all heard the term and we understand the concept. But who's implementing it and what's the best solution?   Are small cell networks being designed without the Backhaul.? Would major carriers make the mistake of underestimating the lack of Backhaul to these sites even in major cities? How will they fill in the gaps, or will they abandon these unreachable locations for more macro sites? These are big questions to which there may be no right or wrong answer. We may have to just wait and see.