Sony RX1 vs. Fuji X-E1?

My understanding is that NR is an algorithm that is applied to the digital file. Whether its automatically applied or user controlled in the camera. 3rd party noise reduction applications have popped up to take advantage of the power of desktop computers to produce superior results to the camera NR.

I fail to see how NR impacts low ISO performance in regards to detail. To me this remark implies that NR is being applied at base ISO. If this is the case surely then there is a degradation in image quality with noise as you increase sensitivity. So if its visible at ISO 200, what's it going to be like at ISO 1600 for example?

Again where we are talking about the base ISO of 200 vs the norm 100 ISO I think this indicates more the sensors ISO performance as opposed to the NR that is applied.

Full Frame vs APS sensor performance is down to the physical make up of the sensor not NR. A wild guess maybe with Fuji cameras, the performance is a combination of sensor design and NR?