This is not a new technique at all
It's funny to see a technique being heralded as 'novel' which has been use for well, I personally have known it for at least 20 years. In earlier days it simply consisted of connecting two dynamic mikes anti-polar (connect the "minus" terminals together, and take the output from both "plus" terminals). The idea is that noise from a distance will arrive at the same time at two mikes next to eachother, thus cancelling out signal in that configuration. Noise from proximity (i.e. your mouth) would induce a difference in pressure and would thus create a signal.
You can still see it used when technicians have to quickly rig mics without the benefit of a sound check or equaliser - just check for mike pairs.
The difference is now that such balancing has to be done by electronics (opamps) because electret microphones cannot be set up in that configuration - until someone gets smart and sticks it in one house..
New? Not by a long shot..