I don't think it's fair to say the author missed this. He seems to be asking precisely if this is the strategy, and if so how well it's working.

> Is that Amazon’s real goal with the Kindle -- is Amazon in the device business only to sell Prime subscriptions, which the company sees as a key accelerant for sales across the rest of its site? And if that’s the case, how well is that circuitous business model working out? Is the Kindle helping to sell Prime? And are those Kindle-fueled Prime subscriptions moving more sales across the rest of the company’s inventory?