Surprise: Apple's Q4 2015 Earnings Report Matters Less Than Usual

I said it on CNBC's Squawk Alley, and I'll say it again: There's a bigger chance than normal that when Apple reports quarterly earnings on 10/27, Wall Street will be disappointed. But in the long run – and by long run, I mean beyond the next three months – that might not matter.

Here's why:

Apple is the most valuable company in the world, because the iPhone is the biggest-selling, high-profit gadget we've ever seen. So the performance of the iPhone, for better or worse, determines the trajectory of Apple's financial results. Other products like Mac desktops and laptops, iPads, and Beats headphones don't really move the needle much because they're relatively small.

A year ago, Apple shipped  39.3 million iPhones in the quarter that ended in late September, up 16% from the year before. Revenue from the iPhone was up 21%. A big part of that? Strong opening weekend sales of the larger, redesigned iPhone 6 and 6 Plus, which Apple said had sales of more than 10 million units in the first three days of sales. 

Not only does that big 10-million-unit pop that Apple saw at the quarter in 2014 get cut way short this time, but also a two-week preorder period means people who wanted iPhones at the end of the month still had to wait.

An oddity of the way Wall Street works is that analysts don't tend to just look at the overall trajectory of a company – they look at how its results look compared to the same season exactly a year ago. And because of two oddities: one in the calendar, and one in the timing of the iPhone launch, Apple's iPhone results have what they call a "tough comp" – a tough comparison to exactly a year ago. But that tough comp has virtually nothing to do with how well the iPhones are selling in the real world.

So what's the oddity? Well, in the recent past Apple has had a week of preorders and just over a week of new iPhone sales in the September quarter. This time around, Apple instead had two weeks of preorders, and Apple's fiscal fourth quarter ended a little earlier than usual, because the last Saturday of the month was September 26. As a result, just two full days worth of iPhone sales are in the September quarter.

Think through what that means. Not only does that big 10-million-unit pop that Apple saw at the quarter in 2014 get cut way short this time, but also a two-week preorder period means people who wanted iPhones at the end of the month still had to wait.

To me, that suggests it will be hard for Apple to show anything close to the 16% unit growth it delivered last year. That's not necessarily because of problems with demand or supply, it's just because of the calendar. Meanwhile analyst expectations seem to have shrugged this off. Consensus is for 47.5 million iPhone units, which would be up 20%. (On the higher side, Drexel Hamilton expects more than 50 million iPhone units in the quarter, which would be a 28% increase. BGC expects iPhone units to be up 30%!) 

Bottom line? Apple might still meet Wall Street's high expectations, of course. Oddly, if that happens, some will say that's bad news for the holiday quarter because demand got pulled forward into September. More likely though, because of the effect I described above, Apple's results will appear to be less impressive than they normally would. But that has more to do with calendars and timing than supply and demand.