It's just running the engines at idle (= minimum power). The idea is that no power is needed until landing. That is what we try and do now, but you have to fit in with circuit patterns and other traffic. All very well if everybody has to get out of their way so they can have a clear unobstructed and unrestricted minimum power descent! But what about the rest of us? We are all trying to do that anyway. It's just a load of hype and hot air. Maybe they are trying to use this as a means 'to get priority approaches'! Not over my ass they ain't!