What is much more likely is that very few people ever get to see these financial models, so many people may actually believe that they don’t exist. But they are there; it’s just that they’re kept on a strict need-to-know basis. I know, because I'm the guy who needs to help keep these models a secret. I keep a paper shredder by my desk at all times, and I don’t ever e-mail this kind of data unless it’s absolutely necessary.
So yes, there are people at Apple who need to make an account for how they are stewarding the gross margins on each product line. Their management of the product line income statement will be a huge component of how they are evaluated for performance and whether they advance within the company.
So just because there is only one P&L doesn’t mean that there isn’t intense scrutiny to every product line’s profitability. These detailed financial models that everyone will use in place of the more generic P&L allow a much more intimate view of all the details. In fact, the scrutiny could be even worse.