WESTCHESTER COUNTY, N.Y. (TheStreet) -- With its decision to take an initial loss for the privilege of selling Apple's ( AAPL) iPhone, Sprint ( S) is larding debt upon debt. The problem, of course, is that until yesterday Sprint was playing coy about how much the iPhone deal would cost.Considering the cumbersome nature of Sprint's existing debt, this is an essential issue. But--somewhat unbelievably--in an article on Sprint's earnings, which were released yesterday, The Financial Times waited until the second to last paragraph to mention iPhone costs. Marketwatch ( NWS) failed to mention it altogether. Even those who mention the iPhone cost issue miss an element that Barron's ( NWS) is right to highlight in a headline: "Can Sprint Sell 25 Million iPhones Over 4 Years?" Sprint's full arrangement with Apple, Barron's posits by referring to an analysts' report, relies on selling 25-30 million iPhones over 4 years. Even the articles that deign to mention how much Sprint is ladling out for the iPhone assume, in the end, best-case-scenario, without giving a sense of just how much Sprint will have to sell to get the full-benefit of the iPhone. Look: considering its debt level, this issue is center to Sprint's future viability. Sprint covers a chunk of upfront iPhone costs for its consumers in order to hopefully make that up--and more--on service revenue. At a recent analyst meeting, Sprint proved so brazenly silent on the issue that the crowd alternated between anger and laughter. Now we know cost--but we won't know potential benefit until we calculate, and track, just how many iPhones Sprint sells.