I think you are missing the point of this and other concepts. What have the recent ones all had in common?
The same 2.5L engine.
Up to now the output was just over 400hp, hinting that this figure is destined for some future RS model. Well now the figure has jumped to 500hp, showing the potential of it ability and be in no doubt that even at 200hp/L this engine isn't some laggy undrivable monster, it's as civilised as any RS car.
I'm willing to bet that this engine will power a longitudily mounted RS model very soon.