Your artcle claims that the infrared camera uses the MT9M001 sensor and RGB input from the color camera features the MT9M112 sensor
According to datasheets, the MT9M001 is the colour sensor with a larger pixel size and not the IR sensor and the MT9M112 is the SOC image sensor more suitable for IR applications
I wonder if the plan was to get rid of the processor but time to market killed that idea and marketing had already set the party line. Still it's amazing companies don't realize everything is ripped apart and posted on the internet, video'd for YouTube and posted on eetimes.
I wonder if perhaps they did not want to take anything away from the 360 system? If they thought the need for an external processor would somehow make the main unit "look bad", I could understand their downplaying the external processing. I can't understand why they didn't just include it in the features for the Kinect and both short circuit all the focus on it while enabling them to say: We have a more powerful system with the addition of the 168? Sometimes companies have sensitivities to unusual things and this could be one of those times. Perhaps, there is concern internally for the 360's processing capacity? Maybe, they are planning an upgrade in the near future and do not want to tip their hand. Just a few questions to consider.
Indeed, almost everything has a processor of some sort in it, and in this case it is a positive selling point. By not sapping the resources of the 360, the fact that Kinect has its own processor is a very good thing -- something to be advertised, not denied.