One of the big question marks around the iPhone 5C – the rumored name for the mid-market plastic iPhone – is how Apple will prevent the lower-cost phone cannibalizing sales of the iPhone 5 and 5S.

One possibility is to limit sales of the 5C to emerging markets. Apple could make it available in India and China, where price is a much bigger barrier to iPhone acquisition, and withhold it from North America and Europe. That would make a great deal of sense, but is extremely unlikely and an approach Apple has ever taken before.

Analyst Gene Munster has another theory, though one just as unlikely: that the 5C will omit a key feature of present-generation iPhones: Siri.

You can almost see the logic if you don’t think about it too much: it’s a core feature of the iPhone, and one that most existing iPhone owners and intenders would not want to sacrifice. As a differentiator between full-fledge iPhones and an entry-level model, it would be a massive one.

But that’s also the reason it seems kind of unlikely. Siri is not only available on the iPhone 5, but also the older 4S, the iPod Touch and the iPad Mini (which could be viewed as the iPad equivalent of the 5C).

Siri is also a feature which Apple has promoted heavily. For a time, it was almost synonymous with the iPhone, and was a feature that other smartphone users envied. But that was then: these days, even pretty low-end Android phones have voice-recognition. Pitching a more expensive phone without it would be a tough proposition today.

Finally, we have to consider the source. Gene Munster’s track-record is, shall we say, less than stellar. There was the Retina iPad Mini he told us was happening in March, the iPhone 5S was going to be out in June, and let’s not forget the Apple HDTV that he’s basically been predicting every quarter since early 2011.

Still, even a stopped clock is right twice a day, so we wouldn’t rule it out entirely, we just wouldn’t put any money on it.