the icon has the hardware to support Nokia Motion monitor "Application uses dedicated core on Nokia Lumia 1520 and Nokia Lumia Icon to off-load sensor data processing from main processor, enabling algorithms to run using low power".
so why not use that core for cortana?
i like cortana but i'm ready to put her back in the box, she is burning up my phone and sucking the battery dry faster than anything i have ever used.
why does quiet hours need her? why?
It's not that simple. Also, Motion Monitor was a kludge of an app, a test bed. It actually kind of sucked. With Lumia Cyan, new drivers will enable full utilization of SensorCore, which is a tech developed with Qualcomm. Case in point, Bluetooth LE? It's now disabled on your Nokia device with 8.1 on it. Reason? Needs new drivers. Lots of things are not optimized in 8.1, that's the whole idea of having firmware in the first place. But you all want the OS first and early, so....thems the consequences.
Re: why not use it for Cortana, there are quite a few reasons, including not forking it due to hardware. The Lumia 520 is 40% of the WP market. It, not the Icon or Lumia 1520, drives the ecosystem. So you build your main functions on the 520, which is why Cortana can run on it.
As a side note: I do find it funny when people in forums, who aren't engineers or develop smartphone hardware, just volunteer tips to companies like Microsoft. It's not that simple to "just make Cortana work on another core". I don't mean to come off as a jerk, though I probably am, it's just these things are complicated and Microsoft often does things for specific reasons. My point is, I write on phones and I'd be out of bounds to tell NASA how to make a better satellite, ya know?