not sure about the clutch
the idea of a centrifugal clutch to control fan speed doesn't seem that great - this requires slippage, and thus wear on the clutch shoes. Besides the obvious issue of this wearing out the clutch shoes quickly, the material from the shoes needs to go somewhere - and since it's in the bowels of the phone, I imagine everything will be quickly covered in powdered clutch material (aided by the airflow from the fan pushing the dust everywhere). Not to mention slippage=friction=heat, which adds to the problem the contraption is designed to alleviate. Not saying it won't work, but surely there are better implementations - at the moment this just sounds like a solution looking for a problem.
<sarc> But hey, who needs a phone that is maintainable and lasts a long time? If a small component wears out you just buy a new phone, right? </sarc>